Pregnant or could this be something else?

The last period I had was 7.20.13, it lasted about a week as usual. Every thing was normal until I didn't get it the next month. I took a HPT about September 12, 15 or so days after my period would have ended. It was negative, but I didn't urinate on it for the entire 5 seconds. I was nervous so I just kind of dripped on it first and then full stream for 5 seconds. I'm not sure if that might mess up the results...A few days after that I started to have brown discharge. It was almost constant for three weeks. It was light and dark. There was a very small bit of blood in it sometimes. Then it stopped for a couple days and I don't really remember but I think it resumed consistently until November 9.

11.9.13 Brown discharge stopped, now clear discharge.

11.13.13 Clear discharge continues, no brown discharge or period.

11.21.13 Pretty sure I have a yeast infection. It is white and left stains on the sheets during intercourse and in my panties. Also, there is pain during intercourse when he gets really deep.

By the way, I don't recall the exact dates but there were some days in April-July that we had sex without a condom, but it was after we did it the first time so he had already ejaculated.  But I supposed there is the possibility of precum.

Also I've gained two pounds in the last few weeks or so, which is odd because I've been consistently 83 lbs for roughly the last half year. So I haven't menstruated in about 3-4 months. At this point if I was pregnant I would probably be showing, right?

I plan on taking another HPT soon, but if I'm not pregnant what else could be going on with my body? I haven't been stressed or overeating as far as I can tell. I don't have any pain, nausea, cravings, or anything. Just what I described above.

I'm just looking for opinions/your experiences (not "go to the doctor" comments). I know you can't know for sure.

Thanks.