Unprotected sex antibitic got my period a week later but 2 and half week

[gokartgirl38]

later spotting light pink? Ok so I was an antibitic for a uti I am on birth contorl. A day after I stop the antibitic I had unprotected sex I got my period a week later frist 2 days we're heavy next 3 were light. Now 2 and half weeks later I'm spotting a very light pink. When I normaly spot it bright red. Could this be a sign I got myself knock up.