I have already removed the back cover to place the battery in. However I need to remove it again to put the sim in.

The battery cover was solid when I removed it the first time, I was suprised and was very secure,

This time its too secure. I cant remove the dam thing, starting to hurt my thumb nail. I have used allot of force before I scream in pain before the phone eats my nail off.

Any help suggestions?

PS. Don't want to damage my phone I have already thought about prising it up with a screwdriver, just one slip and we will be both scared for life