This afternoon I backed up the iP5 in iTunes using encrypted backup. Powered off the iP5 and moved the nano SIM to the SE and powered it on. As it powered up I connected it to the computer and when prompted did a restore from backup. All went well--really surprised. When it finished it had only 23% battery charge so i plugged it into a wall charger and left it alone for a few hours.
This evening I noticed something very strange. If I pick the phone up from my lap or a table/desk the lock screen flashes and then goes back to standby mode (screen off). If I am holding the SE in hand with the screen locked in sleep mode/standby and then tilt my hand (as if to show my palm) again the lock screen splashes on briefly and then off again.
I have never seen this behavior before. Its not in a case or anything. My wife's 1-year old SE doesn't exhibit this behavior. Is this normal? Any sudden movement--and I mean even a gentle nudge--produces the behavior. Wondering if I should take this back to the Apple store and get one swapped out if this isn't normal.