Bleeding but had a faint line

Predicted Period based on App I used: May 25 I had bleeding May 25 afternoon and until now.. May 28 evening. At first I was thinking if it's implantation bleeding... But it got a bit heavier.. heavier than what I expect implantation bleeding to be but lighter than my usual period. I did pregnancy test days before my expected period. It's negative. But I did pregnancy test today May 28 and I got a super faint line. I am worried now coz I am bleeding still. What could it mean? I was triggered to test again because I am feeling pain, dull / ngalay pain on my left hip down to my legs.. so I tested and had a faint line. Now I am worried what's happening.. what should I do.. I plan to tak another test the next day. But for now, I don't know what to do. Thank you!