I play on my worship team at church. I stand between the drum kit and one of the electric guitar players. I have a Fender Rumble 350 amp. I can hardly hear myself but the sound man and the singers on the other side of the stage say that I am way too loud. Actually, the sound man completely shuts me off in the system because he says that if he turns me on in the system at all I overpower everything. Am I doing something wrong?
The first part of the problem is your expectations. As @Zbysek suggested, lower them. In my experience, most people want to hear their voice and instrument about 6-10dB louder than other elements in the mix. If you could instantly shift from a playing perspective to a listening perspective, you may actually agree that you are too loud. This is normal, and something that even top pros have to deal with.
Unfortunately, it's generally difficult, if not impossible for everyone in the band to get their desired 6-10dB. Part of the reason is due to insufficient distances between players. Sound drops off at a rate of about 6dB for each doubling of distance. So if you are 4' from your amp, the guitar player needs to be at least 8' from your amp for the sound to drop off by 6dB. 8' probably does not seem all that extreme. But consider the distance requirements when you have a 5-piece rhythm section, and each person needs 8' or more distance from everyone one else.
Hopefully this helps you visualize the problem (sound sources in red).
Houses of worship are often large spaces with cavernous reverb that takes a long time to decay. Low frequencies tend to rumble around for an extended time. They can build up and mask other important elements of the mix. In really big spaces I believe the low frequencies can build up into a diffuse field. The SPL is constant throughout a diffuse, so if you are too loud in one location, you may be too loud pretty much everywhere.
When you have this sort of problem, about the only available solution available is to put less energy into the problem frequency range. So yes, unfortunately you are probably too loud. Hearing the bass clearly may be important, but it probably needs to be secondary to other priorities (like hearing the melody and words).
The correct solution is acoustic design and treatment. In other words, to create an acoustic space that is more suited to amplified music. Acoustic design and treatment tend to be very expensive, and they can also take away from visual grandeur that a worship hall intends to communicate.