Well, first of all the reason you are probably only having an orgasm from rubbing your clit is because that’s what you’ve been relying on. There are numerous other methods that you can try as well, whether it’s fingering yourself or using a toy, or just humping a pillow. It sounds to me like you’ve found something that works for you, and get frustrated when the other methods don’t work as quickly. So, take your time.
Try to explore your body and find out what feels the best. Also, instead of trying to focus on only coming from fingering yourself and being frustrated when that doesn’t work, finger yourself and rub your clit so that you get the best of both worlds. There are a lot of options, and some work well for some people and not as well for others. In the end, if rubbing your clit is what works for you, then do it, but you can always add something to that so you don’t feel as though you’re stuck in a routine.
-teagan.