do i have battery problems?

[jonnyboi950]

hi everyone im new to the forums and i am so a new andriod user. i just recently got my galaxy s2 for tmobile a couple of days ago and i've been loving it so far. for the last couple of nights i have been losing a lot of battery life while i sleep. i am just wondering if this is normal. i always have full battery right before i go to sleep and when i wake up 9-10 hours later i suddenly lose 10%. i do not have any wifi or data turned on when i sleep, i even turn off all background data and everything. i dont run any apps overnight and i use a static wallpaper. i read around that some people only lose less than 5% overnight so is this normal or not? please help me fix this if it is a real problem. also could it be possible that i need to recalibrate my battery? i read it on another section of this forum. oh and i am running the most up to date version of 2.3.6. thanks for the help.