Allergy to semen.. ugh! TMI

I love pleasing my husband but, I am allergic to semen. I know weird as hell rite? Trying for a baby was so hard for us because everytime I would swell up so bad I had to take benadryl rite after.. (1 year later Im now 5 months prego!) anyways, he loves when I swallow and it turns him on like crazy but when I do I get so choked up and have to take benadryl immediately. He never forces me to but Ik its something that makes him satisfied so I do it.. but, its always so painful for me. Does anybody else have a semen allergy and have this issue? I feel like im crazy!

It is a real allergy, my doctor gave me info on it!