I've never had 'normal' periods (maybe 3 or 4 a year due to type of pill I take) and am now back on the pill so not expecting a monthly cycle, but roughly every two weeks I'm getting a stringy (often bloody) mucus. It's a bit like the mucus plug but not as thick. Sorry for TMI! 
It's as if everything is still 'clearing out' after being pregnant.
I've stupidly Googled it and everything from it being ovulation time to horror stories have come up!
Is this normal so long after a section and should I be worried about it?