It's funny how limitations can really fuel your imagination... I do the same but with time. I have to finish a beat in 30 minutes no matter what. I swear these beats are often better than the ones I take days to make.
you do burn out with everything in your life eventually. there are strategies to prevent burnout but eventually you will burn out its just how it is. the successful people burnout too everyone does but what makes the successful people actually successful is that they come back after there burnout and make the craziest shiz youll ever hear