I need someone to ease my mind

So I am almost 4 weeks pregnant (24th April), I found out 5 days ago (18th April) and 4 days ago (19th April) I started spotting brown discharge with light cramping (like the beginning of my period), I had a miscarriage in November just past. I'm still lightly cramping and still have brown discharge. I'm so scared that it's going to be another miscarriage.

I'm 36. This is my first pregnancy except for my m/c

The lines did get darker and then I ran out of tests so had to order more and haven't taken one since the 19th. I'm absolutely terrified that I'm going to have a chemical even though I've no reason to think it except that I had the m/c before.

Can anyone reassure me? Has this happened to anyone before and it's been fine?

Boobs are a little sore, cramping is in my lower stomach like under my belly. Falling asleep randomly while sitting upright. There isn't a lot of brown discharge and it's only when I wipe (not transferring onto my underwear).