Tender Lump In Armpit. Irregular Periods After Abortion

I had an abortion in Feb. March 30th I had unprotected sex. My third period after my abortion was late. I was 28 day cycle and I m averageing to be every 32 weeks. That scared me bc I ve always had regular periods. I hear that s normal after an abortion but I want to make sure. Than out of no where I woke up with a sharp pain in my armpit in october. It wasn t so much a sharp pain I can t really explain it but I have this pain under my arm. I cnt pin point where it s coming from. There are no lumps that I can feel and it s not sore when I press under there it s just when I do certain things.. the more I keep press on it it s becoming tender so I m trying to leave it alone. But it s just not going away and I am freaked out bc when I Google it nothing but awful things come up such as hiv or cancer . Any advice is very appriciated. Ian a 27 year old woman just in case that helps with any... also if I was hiv would I have a high body temp with that infection in my body? I don t have a fever my temp is like 98.0