missed period, morning after pill, decrease in discharge; help!

Hi, I'm a 16 year old female. In November, my boyfriend and I wanted to use a condom for oral sex. But after my boyfriend put it on, we decided to insert the head in for a little bit. We both loved the feeling it gave us, so we decided to try it standing up but the condom broke. The next day, I took the morning after pill and four days later, I got my period. It's the beginning of January now and I haven't had my period. My period was irregular before the whole incident and I had been to a gyn. who didn't know exactly what was happening. She just assumed stress sometimes played a role and affected my cycle, thus irregular periods would occur. Anyhow, I don't have any pregnancy symptoms. My breasts are perfectly fine, my appetite has not increased at all, I don't have any back pain or mood swings, I don't have nausea or morning sickness. But my discharge has decreased, so I'm getting a smaller amount than I'm used to. Also, I keep getting these slight cramp feelings every now and then over the past few days with a few instances of very slight and short pain. I assumed that my cycle was disrupted due to the pill and is trying to get back on track, but I don't know. I'm trying to get a pregnancy test, but in the meantime, can anyone enlighten me as to what is going on with my body? Am I truly pregnant? What should I do?
Oh, BTW, ever since that incident, my bf and I have never tried that again. We have used it a couple of times since for oral sex and we're always making sure that our hands do not touch each other or our genitals unless we're 100% sure they're clean ie we just washed our hands. Also, I was curious, how long does sperm live for outside of the body?