HELP Pain when I perform Oral sex help!!!

Hey guys I have a serious problem

everytime I try to perform oral sex on my husband I get these really bad and painful muscle spasms, I can only do it for 2 minutes at a time, and boy its horrible!! because when that pain comes its sooo intense and I feel teh muscle moving from the top of my jaw to the bottomw of it, I am desperate since I want to do it more and I love performing it on my husband, I feel so bad about this because teh pain is just too intense and it happens as soon as I suck it a few times, I was thinking of buying a musle relaxant, should thsi work I dont knwo what to do and I am too embarrased to tell this to my doctor!! Helppppp Tweet