About two weeks ago I was prescribed amoxicillin for an ear infection, and i heard that it would effect birth control. I've noticed some spotting recently and I'm not sure if it's due to the amoxicillin or because of something else? I did have sex this month while on the amoxicillin, but we used a condom and nothing broke. I'm just really paranoid about being pregnant, even though it may be very slim.