I had my period for 10 days. Then I stopped. I had sex with my husband and I started bleeding again. Its thin, bright red, and feels watery, way different than my usual period. I've been bleeding for 4 cinsecutive days and it won't stop. I haven't had my period for a couple of months because I am on the implanon. I feel weak and I'm not sure if this is normal or if its something serious.

Normal is a hard term, women are different. If this is not normal for you, then a trip to your doctor for a check up would be a good thing