Pregnant and bleeding

Hi,
I have a quick question. I have a healthy daughter who is 1.5 years old. We started trying for a second baby 2.5 months ago. Unfortunately, the first round ended in a miscarriage at 4.5 weeks pregnant. I found out only about 5 days after conception. The next month, I got pregnant again. Naturally, I was overjoyed. Last Friday, I tested positive with a Clear Blue Digi, showing 1-2 weeks pregnant. I tested 4 days before my expected period. I was supposed to get my period on Monday. I woke up that day and saw blood in my underwear. I immediately thought, no way, did it go wrong again? Sad, I used a tampon (sorry for the details) and still went to work. Two hours later, I changed it, and from then until today (Thursday), there was no more bleeding. In total, 2 hours of bleeding. And my period didn’t come. I’ve been testing every day, and it still says pregnant. Clear Blue now says 2-3 weeks. Of course, this doesn’t mean much because even after a miscarriage, a test can still show pregnant. It couldn’t have been implantation bleeding because I wouldn’t have been able to test positive 4 days earlier. I’m going crazy with uncertainty. I’ve slept poorly for 3 nights and check every hour if the bleeding continues or not. An early ultrasound wouldn’t be useful yet; I’d be almost 5 weeks pregnant now. There’s an ultrasound scheduled for next Thursday, but how do I get through this week? Could I still be pregnant? Or was this a miscarriage? Or a warning sign? The last time, the miscarriage was just a heavy period lasting 5 days. I really don’t know what to think. With my first child, everything went so smoothly. Can someone reassure me? I’ve also heard of pseudo-menstruation. Could that have been it? It’s definitely not contact bleeding because I haven’t had sexual contact in the days leading up to it.