Is yellow diacharge before period normal or a sign of pregnancy?

My period is due in a week and I've been noticing some yellow discharge.

Last Sunday I had sex (with protection of course, no leaks or tears). It was 2 days before my fertile week started (according to the ovulation calculator thing) and then he fingered me some.

I've had some cramps the last few days (I get them a week before my period even starts) but Monday (3 days ago) I noticed some vaginal blood/yellow discharge after I went to the bathroom (#2). Could it just be from straining? Other than that, I haven't really had any symptoms. Come to think of it, I may have an infection because I don't know how clean his hands were (that's gross I know)

But could it be possible to be pregnant even though we were *VERY* careful with the condom and everything? Its just not fair. I don't know what to do if I am. This is only my second time having sex, and by default im really worried.