Need some guidance

I recently just took birth control (Alesse28) and I am worried because I don't know if it is normal to miss period with it. I have felt very emotional and had low sex drive probably with the BC. Now, I don't have cramps, not nauseous, not vomiting, slight pain with my nipples but nothing so serious. I had sex back in December 14 ('twas unprotected) but also he didn't place it in my vagina, it just he cummed on the bed, it worries me that the sperm might swam to me lol. However, I am like 4 days missed period now... Idk if it is just the BC or what. HELP PLS