2nd period in almost 3 years...

Christy
Just a little background so you understand my question:
I found out I was pregnant with my second child in December 2013 and she was born in August 2014. I breastfed her until she was 10months old then she decided to wean herself. I was so excited I wouldn't have to worry about the "weaning fight." So I had a period in early June 2015 only to find out a few weeks later, on Father's Day, I was pregnant with baby #3! I delivered him January 2016 and he just weaned himself 2weeks ago at his 7month mark....so here's my question:
I started spotting yesterday after having some "alone time" with my husband and today was like someone left a fauset on....have any other ladies had similar issues? I had an IUD after my first born so I didn't have this issue then....
**No heavy clots or anything chunky just a steady flow of blood and super annoying cramps with back pain.