I had sex with my boyfriend 6 days ago (2 days after my last period ended) and the condom slipped off. The pharmacist said that it was quite unlikely that i would get pregnant but I took Levonelle-1 emergency contraception 16 hours after sex just for piece of mind. I had no side effects except for a slight headache, but now, 4 days after taking it, i am having slight cramps and am experiencing spotting. Is this normal? 

Also, we had sex at 12 days and 15 days BEFORE my last period. We used a condom both times, but condoms arent 100% effective. I took a pregnancy test before i took the emergency contraception (on the same day, so 4 days ago, about 3 weeks after sex and 4 days after my period) and it came back negative. So the bleeding and cramps that im getting cant be due to pregnancy right?

Thanks :)