when i manage to sneak up on someone sleeping to feed as a vampire at night the only options are to pickpocket in sneak or if i stand then it just says talk,how am i supposed to feed?

Are you sure you are a vampire yet and you don't just have the disease that causes vampirism in a few in game days?

If you just have the disease just wait a few in-game days to become a vampire or use a cure disease potion or activate one of the shrines of the divines if you don't want to be a vampire

No idea. Never happened to me before.

yes im sure tried cure poison and disease and the shrine of talos,have the invisibility perk and so on

No mods?

im on xbox so dont think that apply's does it?

Your game might be bugged then. When in sneak you should have the option between pickpocket and feeding for a sleeping NPC.
Did you try feeding on a different sleeping NPC?

Also, you have to click the A button for pickpocket first before you're given the option to feed

thanks for all the help but dirtnap,im such a [censored] i didnt even think of pressin pickpocket,worked first time,i fed 5 times on my prey will that b enough to go thru the day?h

You will only need to feed once per 24 hours.
If you dont mind becoming a higher stage vampire, but dont want to be stage 4, 3 days.
If accidentally you do become a stage 4 you will be attacked by NPC's. Travel to a farmhouse or a remote dwelling like the hunter's rest and be sure to arrive at night when your prey will be sleeping.

where does it tell you what level you are,i fed 5 times on one person and falion still has no option in the dialogue when i approach him about being a vampire

You will need to be referred to Fallion first.
Talk to any innkeeper.

You can probably gage your vampiric level in your active effects.
When you advance a level in vampirism, it will also be displayed on the game screen.