Advice needed, possible TW

I’ve known I was pregnant for 4 days now. I woke up this morning bleeding (pinkish red but not bright red if that makes sense) so I tested again today and the line was there within seconds and this is the darkest line I’ve gotten in the last 4 days. It was there within 15 seconds after the dye ran. I have a history of MC, but getting a line this dark after I’ve gotten lines that weren’t even hardly there, I’m not fully convinced I could be miscarrying. What else could cause the bleeding? (I haven’t been sexually active in any way since I found out)