late period?

[br04]

On July 3rd, my boyfriend and I had protected sex, but the condom was taken off after he pulled out and began to masturbate, and he was cumming, but a little bit got on the top of my vagina. It wasn't far from the opening, but I wiped it off right away & before it ran. Later, he had just wiped off a little bit of precum, waited 1-3 minutes, and then touched my vagina for a split second. I've been very nervous, I really do not want to become pregnant. My last period was June 9-14, and I'm on a regular 28 day cycle, meaning I was due again yesterday. However, I did begin taking ciprofloxacin. I was having pms symptoms before I took this medicine, but now they're gone. I read online about other women with this problem, who were up to a month late for their period. I'm younger than normal,  and I know it was wrong and that I shouldn't have done anything to put me in the situation. But how much of a risk am I at for being pregnant? Could my period just be delayed by the cipro?

[br04]

Also, I have had gas & constipation, loss of appetite, bloating & acne. These could be both pregnancy & pms symptoms, but it's only been 5 days since intercourse.

[br04]

I was also put on the cipro because I had a severe uti.