Well, first, you really need to get yourself a real bass amp/speaker. The purpose of an electric bass is to produce "low and loud"you' sounds, so if you're using speakers that can't do that, you're missing the whole point! Even a small, inexpensive combo amp will be much much better than your stereo speakers -- and you're much less likely to accidentally damage it by playing too loud and low. Also, it is difficult to properly practice your technique if you can't hear yourself well enough, as you can't really tell if what you're doing sounds the way it is supposed to. Until then, do you have some decent headphones? If so, use those instead of your speakers.
Second, if you really want to learn how to do this, I recommend that you do exactly the opposite of what you're trying to do now: You should practice entirely on the A, D, and G strings, and avoid the E string completely, until you get your plucking technique right. It appears that the technique you are using to pluck the E string doesn't work on the other strings, so you need to learn how to pluck those other strings. Then you can work on plucking the E string in the same way.
Third, yes: you only have to "lick" the top of the string. That's a pretty good word, actually -- though not in the meaning that's usually associated with bass or guitar (i.e., "to play a lick"). In English, to "lick" something is to use your tongue to, for example, taste it, as you might do with an ice-cream cone, or the way a cat or dog might lick your hand or face. You don't need to push the string down, or even really pull on it; you just need to make enough contact with it to make a sound. If you do this gently it won't make a loud sound, but that's what your amp is for.
Does all that make sense?
