URGENT PLEASE HELP!

I’m 22wks 3days pregnant and I just went to the bathroom and found this in my underwear when I got up there was a small sized maybe dime sized clot in the toilet. I’ve also had some stomach pain for the past two days but my doctor said it’s nothing to worry about. I just called my doctor but the answering service said they were at lunch and to call back at 1:00pm. I’m freaking out could I be miscarrying?