help idk of I'm pregnant

So idk if I'm pregnant .My boyfriend and I had sex like around early September ,and a week after my period was suppose to didn't ,but once in a while  it skips until around this time the 23-28. I'm not feeling dizzy or any other sickness or increase in appetite ,but I have been gaining weight (I was thinking it was because I work at A fast food place and I'm always stress with school),but I'm having like white discharge but not like a lot just the usual. I haven't taken a prenacy test yet (I'm to embarrass to go buy one) I'm so scared -Do you think I'm pregnant ?