First of all you should be extremely happy, as most if not all hospitals prioritise their placements for 3rd year students, so consider yourself really lucky to have a placement in your second year.

Incidentally after my planned hospital placement fell through last summer I contacted Bham + Solihull Mental Health Trust for some pharmacy related volunteer work to be told they weren't taking on any volunteers

Still managed to get a placement last minute though.
You don't need to be worried at all about a pre-reg placment, as when you apply next year you would already have had at least one placement in hospital - many hospital pre-regs have no experience at all before they were offered a place. If I were you I would apply for another placement when you start 3rd yr - if in brum then best bets would be university hospitals brum nhs trust or heart of england nhs trust as you could get a pre-reg with them if you shine in the placement. You sound motivated enough to work in hospital and the dedication's paid off for the placement anyway !

If you need any info regarding placement/pre-reg applications the PM me.