3 weeks PP after c section

So I had a c section 3 weeks ago as of yesterday. I had very little bleeding for the first couple days (maybe a couple of drops) then nothing. Haven't had any form of bleeding or cramps. Last night, my husband and I decided to be intimate, but go slow... I know it isn't 4 weeks yet, but it's Valentine's Day weekend. Afterwards I noticed a little bit of blood when I went to the restroom. Now today I'm having heavier bleeding and it is a dark red/ brown color.