iphone 5 flasing on video player?

hi just got my iphone 5 5 days ago

i just got a very minor problem but very irritating

so here it is

1st battery: but i already fix it by settings my iphone 5 last for 10 hours texting and ipod music maybe it can last 2 days if i dont play games like asphalt and brothers in arms is it normal? i play maybe 30mins all in all cause i stop after i finished 1 stage

2nd:flasing/blinking on video player? before playing the video the point when you will choose what vid you want to play it blink sometimes may be after 5 tries of opening video player in flash/blink on left side only