Giving blowjobs

I need help ASAP! My boyfriend and I have decided to not have sex anymore, for multiple reasons. We’re just going to stick to things were his penis isn’t inside my vag 😂

But that brings up the issues or oral. He is amazing at it. I, on the other had, struggle and I always seem to disappoint.

First I have a very small mouth, which makes it hard to get in my mouth at all and leaves no room for me to use my tongue. I also have a horrible gag reflex, and TMJ. If you don’t know what TMJ is it’s a jaw condition. So sometimes my jaw locks, and it’s sore all the time. So giving head is pretty painful, and if I do it longer then a couple of minutes, my jaw is messed up for a few days.

Any suggestions on what I can do??