Overall I think you have nice tone, but you really appear to be tormenting yourself.
My suggestion is look at your face and nonverbals and consider how much tension and self judgement you are bringing to your playing. IMHO, These are things you must learn to free yourself from as they sap you of energy and focus. Clenching the jaw, shaking the head, and thinking negative thoughts does not help you make beautiful music. In fact, you can literally see the anticipation of some of your mistakes before they happen. The tension comes over you and then the mistake happens. To help overcome this, perhaps you could break down the problem areas into smaller bits, slow them down, and play them in until they become easy and automatic.
Also before starting a problem section, and occasionally between repetitions, take some time to visualize playing with a positive outcome. Imagine the voice of your instrument and the sounds being drawn effortlessly from it. You may want to practice playing long tones to get the idea...breath and be one with the instrument. You can also hum or sing through a section if you can't hear it in your mind, but the main idea is to try and think about how it feels to move your fingers and interact with the bass while imagining or humming the notes.
Visualization should help you form a link between the notes on the page, muscle memory, and the resultant sounds emanating from your instrument. The goal is to simply "do" rather than thinking about playing so much. Visualization is also believed to build confidence. It's sort of a self-fulfilling prophecy. If you expect a positive outcome, it is more likely to occur, and if you expect a negative outcome...well you get the idea (Oops

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The way I like to work out music is to identify problem areas for focused study. Then I will work through each problem area for an extended time until I start to hit the wall. Before I get too frustrated and tense, I move on to the next problem area. Eventually I work through all of the problem areas and go back and start cycling through each section a second time. You can work through the sections in the same order or mix them up if you like. Eventually you will feel you have mastered some of the areas, so you can set them aside and continue cycling through the other areas that still need work.
Each time you start an area, drop the tempo down so you can focus on playing properly. You will repeat this section of music several time before you move on. As you become more proficient, you should be able to increase the tempo a little each time you play through it. Sometimes you may bump the tempo to far, which can cause you to stumble and have a setback. That's okay. Knock the tempo back a few clicks and keep working. If you can work it up a little faster on this cycle, great. If you start to get too frustrated, let it go and move on to the next section.
I usually move to the next practice area when I start to get frustrated or can't increase the tempo any further. When I come back to a section, I have to drop the tempo down a bit from where I last left it, but the tempo is usually higher than it was when I started the section on the previous cycle.
The goal is to play in tune, with proper intonation, dynamics, and phrasing at a tempo that is slightly faster than required. Once this is achieved you can consider the section mastered for the day and drop it out of your cycle. You may not master all areas in one session. When you start to become fatigued or lose focus overall, it's time to take a break.
As an observation, you are not using any dynamic shaping with this etude. Perhaps it would be helpful to have your instructor write in some dynamic shaping for you. The idea is to make music even when playing an etude, which should make the experience more enjoyable.
To work on intonation, it can be helpful to use a tuner that has a tone generator. You may want to discuss this with your instructor as not everyone agrees with this idea. I think my favorite is to set the tone to the fifth of the key I am playing in. My second favorite is to set the tone to the tonic. It can be interesting to try with the tuner at other intervals as well. Of course, depending upon the passage you are playing, some reference tones work better than others. Playing with a fixed reference pitch does not necessarily teach you how to properly temper pitches, but it does get you in the habit of playing against another tone and adjusting, so that you are in tune.
Just for context: Later as an advanced player, you will probably want to research and memorize some rules on tempering. Keep in mind a tuner is setup for equal temperament, but when you play upright you will have a tendency towards just intonation except when you use open strings. Essentially you can learn to intentionally play notes flat or sharp based upon how they relate to the overall harmony, and this will make the sound even sweeter.
I hope some of these ideas are helpful and sorry if I went on too long

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