I think Facebook takes practice however you use it…it really isn’t easy finding your way round all the features, then it seems to happen gradually. There must be a flag, probably red, on the toolbar with a number on which tells you how many notifications. It may be that you haven’t had any notifications, so there are none to see. It should be clear when there are some. It is a good idea to pop back in the shop where you bought it..after sales support varies but some can be good. Or phone your supplier, they usually help with most things.
Personally I think the best way of getting help is to take an hour train journey! seriously, they are all using Blackberry’s –on facebook and swapping ideas about how it works. Even your local diner, if it is friendly, not posh.