Welcome to the forum. I'll try to help.
Your symptoms strongly suggest an initial throat infection (pharyngitis) of some sort, and your doctor agreed, otherwise he would not have prescribed penicillin. As you probably realize, the symptoms and signs of pharyngitis are pretty much the same regardless of the cause -- and there are many, many causes. Allergy alone is one of them, although allergy usually would not cause the severe symptoms and enlarged lymph nodes ("glands") you had at the outset.
STDs are among the possible causes, but probably not in your case. Most likely the pharyngitis was just coincidental at that time, not acquired by the oral sex event. The two most common STD possibilities are herpes, as you suggest yourself, and gonorrhea. Gonorrhea of the throat usually causes no symptoms at all, and most cases (although not all) would have been promply and completely cured by penicillin -- and it's pretty uncommon anyway.
And initial oral herpes usually causes not only sore throat, but also multiple sores in the mouth, i.e. of the cheeks, gums, etc. Equally important, herpes doesn't last this long; even without anti-herpes therapy, your symptoms would have cleared up entirely long before 3 months. Finally, you are exactly right about genital symptoms: in someone who has had both vaginal and oral sex with someone from whom they catch herpes, it is unusual to become infected only orally. It's possible, but not very likely. So all things considered, probably this isn't herpes. However, it's still a small possibility.
Mononucleosis is a possibility. Most doctors would have done a mono test in a patient like you, so maybe that was done; if not, ask your doctor about it. Although often called a "kissing" disease, mono in fact usually is an STD. Most people with the mono virus have no symptoms, so this is a possibility even if your partner has remained well.
Bottom line: I'm reasonably certain you don't have herpes, but it's somewhat possible. Discuss it with your doctor; it's too late for an accurate culture or PCR test, but a blood test for HSV could help sort it out. Also, you should speak with your partner and make sure he doesn't have known oral or genital herpes, if you haven't already done that.
I hope this helps. Best wishes-- HHH, MD
Thank for for you prompt reply.
I had an STD screening last week, and everything came back negative. However, my dr has not wanted to do a herpes blood test because she believes it will come back as a false positive.
Also, I had mono about 9-10 years ago. Can't a person only get it once? I usually always get sick around that time of year and grew up always getting strep throat.
My partner at the time, also got sick at the same time i was. Same symptoms, sore throat, stuffed nose - but not sure if he had the white spots on him throat. For both of us, it lasted around a week. My white spots were only on one tonsil, no where else in my mouth.
I'm sorry you didn't say anything about your partner's symptoms originally -- my reply would have been shorter. Obviously you were shaing some sort of garden variety upper respiratory infection, not an STD. White spots in one person and not the other doesn't mean anything, and it doesn't particularly suggest herpes.
Correct, you can catch mono only once.
I agree with your doctor that there is no need for an HSV blood test in this situation. If there were serious suspicion of herpes the test would make sense, and most likely your doctor would agree. I doubt the risk of false positive result was her only reason for advising against it.
It sounds like you have a doctor on top of her game. You can trust her advice.
Thanks for all your help Dr Handsfield,
This is something I definitely have anxiety about.
As for my swollen throat, I'm going back to my internist for a checkup after finishing up the penicillian.