I'm sorry to hear that this causes you so much anxiety and it is hard when you have people in your life you worry about. But you have to let this go. A condom break is unfortunate but a one time unprotected sex is very low risk to begin with. And now, you've tested negative. So, you do not have HIV. It is not going to change. You would have to be taking well above the recommended dose of biotin to have any interference. If you are simply taking supplements in a regular manner, it will not interfere. Only those recommended for hair, skin and nail growth have the higher biotin concentration. I don't know the mg you were getting each day but it is unlikely you were taking more than the recommended mg per day amount. Flonase has no affect on HIV testing.
Lots of things cause swollen lymph nodes. I have one now myself because I was sick 6 wks ago and it hasn't gone away. Just having a swollen lymph node from time to time is not unusual or worrisome. It's your body doing it's important work.
Personally, I would move on.
Yes, I just got the oral part. But still no worry because you have tested many times with negatives. If you took a 4th generation test at 50 something days and it was negative, that is all you need to confidently move on from this worry. You do not have HIV.
Oral sex is not, repeat NOT, a risk for HIV. You never needed the first test you took let alone all the ones after. Saliva and air inactivate the virus. The only way adults get HIV is unprotected vaginal or anal intercourse and sharing IV drug needles.