Pregnancy Aftet Miscarriage ?

I Miscarried Around June 20 , I Had A Normal Period On July And August . August 25 Was My Last Period And I Haven’t Gotten It Since . Took A Pregnancy Test Indeed It Was Positive. Ive Been Scared Because I Have Alot Of Hip & Lower Backaches And Did Have A Little Spotting At the beginning of this month but nothing since . When I Miscarried I Was Having Alot Of Bleeding And Extreme Back Pains. Now Im Scared That I Got pregnant To Quick And That I Might Miscarry Again. The App Says Im 5 weeks pregnant But I Haven’t Went To Get Check Out. Any Advice?

( I Haven’t Went To Get Checked Out Because when I went to the emergency room because of my back pain and bleeding and the doctors told me i had a UTI and gave me antibiotics, During The Visit I Got An Ultrasound and the told me baby was fine and the heartbeat was strong. I started to take the antibiotics and 2 days later i felt worst and miscarried)

Also:

Ive Been Feeling Like My Stomach Is Going To Fall Off My Body When I Wear Tight Clothes It Feels Better Is This Normal?