You say you "just upgraded" ... how long ago? ICS optimizes your phone, and that can take a while, during which time battery life can be poor and the phone operate rather funky.
search is your friend; it's been talked about a lot in several threads on this forum
give your phone at least 72 hours to optimize and see if the performance then doesn't improve
I have a Lucid and actually my battery lasts 50% longer. When I upgraded I had to go back and disable background data and of course all the apps I had turned off turned on again. Also I had to go back and reset set apps to not auto update. Also with ICS it has this feature where you can disable many of the bloatware apps so they never turn on again. Not as good as deleting them but better than not having to force close a billions apps on the occasions I have to turn background data back on for a few minutes.