Sanyo M1

okay, i use the heck out of this phone. at least 3,000-4,000 text messages a month and about 2,000 minutes a month. i've had the phone since February 1st. beside the loose hinges (which i noticed, but i see that its not just my phone but all of them thanks Sprint74) but my battery cover is also loose, its raised about 1mm and i am able to push it down but it always pops back up (it still is operable, but its annoying when i'm texting and my battery cover keeps slipping) do you think the extended battery can fix this problem? also, i don't know if its related to the battery, but my phone shuts off if i open my phone at the exact moment that my phone receives an alert, is this common?