PLEASE HELP!
Hi everyone. I'm in desperate need for some help at the moment.

Let me give you a bit of a background...
I've been on the pill for two months now(well I'm on my second pack).(28 day, I start on Tuesdays) and during my first pack I bled almost continuously throughout the month. I had protected sex during that month and I got my period on the placebo pills right on time. I started my second pack after my week of the placebo pills finished/period ended, and everything was fine! This month, however, I noticed a pill on the floor, about a week into my second pack. I take the pill religiously each day because of an alarm on my phone, and I instantly checked my days. Each of them I could account for taking them this cycle so I'm assuming the missed pill was from my first pack. I only recount taking one pill late in my first pack and otherwise they had been taken each day at the same time of 6:15 pm.

At the end of my second week into my second pack, I had unprotected penetration...ish. He tried to get in, but I was way too dry and I think maybe the head (at most) barely got in. We stopped after a few seconds of useless thrusting, realizing that wasn't going to work and we moved on. Later that night we had protected sex twice, both with a condom. He withdrew each time before he came, however, and held the base of the condom as he did. The condom did not have any breaks and we put it on correctly.

5 days later and here I am, paranoid to hell! I think I have a slight cramp every once in awhile in my lower left abdomen but it's barely noticeable. My lower back, shoulders and neck have been aching just today so that has gotten me worried, however I have NOT noticed any enlarging of my nipples or areolas. I have been extremely stressed because of this and I'm so afraid this could be a pregnancy. I have not had any bleeding since the intercourse, but I am expecting my period Tuesday.

My anxiety levels are off the charts right now and I think my paranoia is getting the best of me because I can barely concentrate on anything else besides being scared. I also had a job interview today so that did not help my stress level at all.

Should I take my placebo pills today to see if my period will start early? Or do I really have nothing to worry about. I'm so scared because I will be 18 in two weeks and I really cannot afford to be pregnant. Also, if I do attempt to start my period early and it doesn't work...what should I do?! What are the chances I am...eeek.

Please please please help! I have a surgery Monday and they test for pregnancy beforehand...I can't tell you all how horrific it would be for them to walk into the room and say something like they can't do the surgery because ... I can't even say it. Please help!