36 hour period?

Kelsy • Wife to a wonderful husband, mommy of a toddler.
Has anyone had a 36 hour period? I normally have a textbook cycle as in, usually every 28 days and ovulate on approx the 14th day then bleed for about 5 days. However this cycle I started my period a day late had my normal horrid cramps but only medium bleeding and it just kept getting lighter. It's only been 36-48 hours since I started but it seems to have already stopped. I've never had this happen. I got a bfn the day I was supposed to start so I'm thinking I'm not pregnant. No new stress, weight change or any normal explanation for what's happening. Just wondering if anyone has had the same thing? Thinking of calling my doc even though I hate going...