The pill and bleeding

I recently started taking the pill again... The kind you take for three months than have a period.
I've been taking it now for two weeks and 3 days. So 17 days.
My period started on Sunday February 1st so that's when I started taking it. My period lasted a little normal than longer but I assumed bc of the pill.
Now everytime I have sex with my boyfriend I bleed a lot... Like clots sometimes. And it's really embarrassing and strong smelling, which isn't normal for me.
I would like to be able to get back to having nonselfconcious sex with my boyfriend without this being a worry.
Any advice or idea of why this is happening or when it will stop???