Heavy bleeding for 3 months despite medication—has anyone experienced this?

I’m a 25-year-old female, and I’m wondering if anyone has experienced something similar.

For the last 3 months, I’ve been getting my periods with an extremely heavy flow. The last time this happened, my gynecologist prescribed medicines to reduce the bleeding, but they didn’t work at all. The pain was so severe that I had to get painkiller injections for relief.

I also had an ultrasound, but everything came back normal except for PCOS.

Now it’s happening again. I’ve been bleeding heavily for the past 3 months, and I’m feeling extremely weak and exhausted. I’m really worried because no one seems to know what’s causing it.

Has anyone gone through something similar? What was the cause, and what helped? Any advice or shared experiences would be greatly appreciated.