I'm so sorry. I hope it turns out the way you want it to.
If you have a midwife, they can help with natural options over the pill (and the it's harsh side effects). My close friend just had a loss, her body took 2 weeks after she found out. She was glad she let her body take lead, over the pill incase the findings were wrong.
I'm sorry your going through such a stressful time. If your HCG levels at least double every 48hrs then It could be that the date of ovulation/conception is off and your actually not as far along as the calculation from first day of last period. But if your sure of your dates the chances miscarrying naturally will occur before or by 12weeks. Again, I'm sorry but keeping my fingers crossed for you x