Tried calling doctor, but no answer and Google is no help

Kristlyn • 21.—Married to my Best Friend.—Mommy to T.A.J.👶🏼—👼🏻x3—awaiting 🌈👶🏻

Me and my husband have been trying to conceive for the past two months and I've already had one chemical pregnancy.

I just had a baby on July 3rd (via c-section), and my doctor told me it was completely okay to have sex and get pregnant again (if we wanted to) after 4 weeks (if I was feeling like it, and I was. I've tried calling my doctor again to ask her if I only had a chemical pregnancy due to pretty much just having a baby, but she hasn't responded at all. Me and my husband have been having sex almost everyday and last Thursday I just decided to go and get on birth control because maybe having another baby wasn't right for us. So I got Paragard (the copper IUD) last Thursday, but before I went and had it done, I took two pregnant tests (first response) and both came out negative.

Could I be pregnant and it was just too early to tell? Or if I was pregnant did the IUD cancel it out? Or will something be wrong with me or the fetus if I am pregnant? I'm scared and if I take another pregnancy test and it says I am and I have a miscarriage or another loss, I don't know how I'd feel.