My gf and i had protected sex on march 6th and the condom broke. Within one hour of the accident she took the plan b pill. She got her period on time, however it was heavier than normal for a few of the days. We assumed that this was ok. Since then she has had some occasional spotting, and she got a 2nd period that lasted that lasted 7 days and came one week early. this period was lighter than usual. She is irregular and has spotting often. Over the past couple of days she has had back pain on and off. It is there one day and then goes away and comes back a couple days later. Also when she fingers herself she notices a small amount of brown discharge later when she wipes and once when she had an orgasm. Is this old blood from her last period or something else. Could the back pain be related to an infection, pregnancy, or just long term effects from the shock of hormones from plan b? She keeps telling me everything is fine but I keep worrying about it. The discharge i'm talking about started about 5 to 6 days after her period and she notices that a day or so after it appears it turns clear again, and only is brown after being fingered. Has anyone had this experience?

I did not ejaculate inside of her so there would only be precum if any.