Pregnancy after miscarriage

I am 3 days late on my period and this would've been my 2nd period since my miscarriage in April.

Previously I had said that I would wait until I missed 2 periods before I took a test just to be sure...but now I'm rethinking that.

Should I test once I'm a week late, so that if I am in fact pregnant I can start taking a hormone pill?

I guess I just don't want to get my hopes up and have a negative test OR get a positive and something happen....I am so very nervous and can't seem to think of anything else! Any suggestions?