Just got my BFP

Just got my BFP today but I had back surgery in June and only had my period in July and it has been all crazy before surgery and after surgery, I went to the doctor today to get put on medication to regulate my period and I have been on pain medication since surgery as I need another back surgery, the doctor asked for a urine sample so he can check the urine prior to sending script and I left his office, a few hours later and he called me and asked me to come back tomorrow as he got a faint positive and if it was positive it would mean that I had gotten pregnant in July, I went and bought a pregnancy test a the suspense was killing me and within seconds the test read pregnant!!! Now I’m nervous because I had no idea I was pregnant and have had so many test done since July and have been on all this medication and they are guessing I am 13 -14 weeks along! Any advise from anyone would help, but please be kind as you need to remember I had no idea I was pregnant as I had irregular periods and was going to the doctor today for medication to make my periods some what regular to try to regulate them and when I started that I was going to talk to my PCP about coming off the pain medication! I feel awful knowing I am now in my 2nd trimester!!!