possible miscarriage? please read

For starters, I use this app to track my cycle through bbt. This last cycle was very odd. About halfway through my cycle, but a few days before I was scheduled to ovulate, I experienced bright red bleeding on and off all day. It was heavy enough that I had to use a tampon. (I know that some women have spotting about ovulation, but I have never had this occur before.) Then, a few days later, after I had ovulated (according to the app), I had spotting again. It was bright red this time as well, but it was much shorter, lasting only 30 minutes or so. From then on, I began feeling very off. I kept getting dizzy and having annoying headaches, nearly every day. I kept feeling nauseous, on the verge of puking, at least once a day. I felt exhausted, regardless of how much sleep I was getting. I know that (while not always the case) most of these symptoms can serve as signs of an early pregnancy, but I decided to wait for my period to come before I tested. My expected Period date came with no bleeding, so I told the app that I was late, and it rescheduled it for 2 days later. The new date came and went, again with no bleeding, so I decided to take a test the next morning. To my surprise, it was negative. 2 days later, I woke up at 5am with very painful cramps and heavy bleeding. This continued throughout the entire day, and my mom mentioned that I should take note of what it looked like. When I finally checked, I noticed that it was very bright red again, but much chunkier than normal. The bleeding was so heavy that day that I doubled my typical tampon use for the day. My mom thinks it could have been an early miscarriage. I have never been pregnant before, so any insight would really help. Thanks in advance! 💕