Scared need support

So I called my dr because AF came a day early and it's been really heavy. I went through a box of tampons in 1 day, extreme pain, and Midol isnt taking care of the pain. She told me I need to take a test and see if I have HcG because I could be having a MC. I'm freaking out right now!!!!! Please please please pray that it's just a really bad period and not this. The fear is overwhelming! Do you think it matters if I take the test now or wait till morning? Sorry for the crazy text I just never had this sort of fear before.