Period abnormalities

Stephanie
Ok, so I have been on the pill for years (probably too many) due to irregular periods. But since I've been on the pull I have never really had any problem with it until recently. Since June, every other month I get spotting for about a week before my period starts. I'm not missing any pills. 
I don't know if it's related, but I just started having sex again after a few years and it was painful. I went to my gyno and got external and internal ultrasounds and she says the results were normal and "beautiful" (her words). No cysts, no polyps, nothing. 
The spotting isn't heavy but just a nuisance. Anyone have any ideas?? Thanks in advance!!