What Causes Swelling In Tonsils Post Having Oral Sex?

I think I have herpes, but I am not sure. I had oral sex for the first time about 4 months ago, and I've been having symptoms in my mouth since 2 months ago. He did not ejaculate, but he did pre-ejaculate. My tonsils have become very swollen, however, the swelling on my left side has gone down while the right side has remained the same. The skin on the corner of my lips has become very dry and itchy, as well as red. About three years ago, my lips had the same symptoms with no sex whatsoever (4 months ago was my very first time). It all began with my tonsils becoming red and inflamed. Sometimes I believe it is psychosomatic because the symptoms appear a couple of days after I researched them. I keep coming to three results: tonsilitis caused by infectious mononucleosis, herpes simplex 1, and strep throat.