the first few times that i had sex there has always been a little doubt in my head that i could be pregnant.
weather or not there is a condom involved i just freak out sometimes.

to calm my nerves about being pregnant what i do, is think that i'm not pregnant unless i miss my period which i never have.
i focus my mind on other things.

you posted this awhile ago, and i would love an update on what happened

Hi,
I've been in your shoes once. It's normal to get nervous about being possibility pregnant. I don't think burping is a symptom; Nausea is a symptom but, you can also get a little nauseated while coming on you period. Now when you had this bleeding, was it normal for a few days or was it just causal spotting. If you're having really big worries about maybe being pregnant I would either take a pregnancy test or head to your doctor and get blood testing done depending on far back you had the sexual intercourse. I've been told by my doctor that any testing before 4 weeks with a HPT. [ Home Pregnancy Test] Wont show up and the best bet is to get blood testing because it will definitely tell you for sure.

Once you find out if you are or not. If you are you need prenatal care, Talk to your OBGYN about your opinions; [Abortion, Adoption or Keeping it] Just know the doctor or any of the support leaders or members of the forum can't stir you in any direction. You and your partner need to talk about it [with your parents if your underage] and come up with your decision.

After having sex with my ex I had the feeling, I knew i was pregnant and the things I did to calm my nerves about taking a test or being pregnant was just trying to think positive.

If you need to talk to someone don't be afraid to PM me, and I'll give you my aim scree name to talk personally one on one.

I hope this helps,
Good Luck with whatever you decide to do!