Due around 8/17/18 but .........

I got a positive pregnancy test 12/21. 12/24 night I had bad cramping and started bleeding ( light but had to wear a tampon) and I am on day 5 of having to wear a tampon for bleeding. This would be by second child I did not experience any of this with my 1st. I cant get into the doctor until 1/9. I know if it’s a miscarriage they can’t do anything about it.

Had I not just happened to take a test just in case before Christmas I would think this is a normal period!

Thoughts ?