Help!!! Extremely worried

KT

So I thought I had a chemical pregnancy because my lines were extremely faint for seven days and then I started bleeding heavily. Fast forward to what I thought was cycle day 3 and I get this strong urge to take an OPK because I thought I was having super early ovulation; my boobs were still really hurting and I’m having numerous cravings and unbearable hot flashes. The test line got so dark it pulled from the control line... That’s weird, I thought. So I get out a cheapie just for the fun of it and there ends up being a distinct line! Thinking the test is faulty, I take another cheapie; same line appears! So I take a digital and it says pregnant!!! How is this possible?! I bled heavily for two days with horrible cramps, it’s just spotting now but I don’t know how this could still be a viable pregnancy. I’m scared what this means :( I’d be 20 DPO.