I need answers advice...

Jenna

My last period was November 21st had slight bleeding Dec 13th which wasn't even enough to fill a liner and negative test yesterday but been having light pink and a browny red for 3 days before test and still today so 4 days straight now but no period still at all, the blood isn't even enough to completely fill a liner do I don't know what to do or what's going on and recommendations or advice to help or answers to what's going on? I'm only 18 and haven't been smart :(