Help battery drain 90% in a minute?? wtf

This is the second time something like this has happened. Ive had the phone a month.

The first time it happened i loaded a graphic intense game.. it froze for about a minute, ibpopped the battery out and rebooted. Noticed battery dropped from 98% to 35%.

Ok so just now i tried to load a large movie im still downloading. The movie is about 3 gigs. the movie wouldnt load after a minute, so i returned to homescreen. Everything running slow. Tried to shut phone off, not working. Popped battety out. Reboot. Battery now says 8% when before i loaded the movie it was 100% and still plugged in charging.

How in the world can the battery drain so fast? The phone has frozen plenty of times before but so much power didnt magically disappear. Wtf


What else was running on the phone at these times. Some other intense programs or apps. I guess it's possible the battery is no good. I'm just guessin here btw but who knows It may help. I would have the battery replaced and see if that helps. It should still be under warrantee is it not. ??