iPhone 3GS charges up to 1% and instantly dies, boots repeatedly

So I recently bought a new battery for my iPhone 3GS claiming to be a 1600 mah battery. However, when I installed it into my phone it was stuck at 69% so I tried to charge it to 100% to calibrate the battery. But it stayed at 69% I played a 10 hour long video till it finally died (oddly enough still saying 69%). So I charged it again but it was at 1% with the little outlet logo instead of the lighting bolt logo. And then it died again tried turning on by booting showed 1% and died. I have recently removed an ifixit battery that it previously had that expanded I don't know if it could have damaged the phone in any way. And the last time I checked it, it said 100%. But as soon as I unplugged it, it died. What is going on with the phone?