Implant...and period

I got the implant about 5 weeks ago I think.
 I started my period on the 15th...my period still hasn't ended.
 It was very very light for a few days so my boyfriend and I decided to have sex. After that it was super heavy and bright red. 3 days ago it went back to light so I thought it was going to end but still didn't. So we just went with it and had sex again and now it's really bright red again. 
Is this normal? Should I talk to my doctor?