Well, yes, that's a worry of lots of diabetics I think. You're nowhere near losing your feet or toes though, don't panic! In all seriousness, you should treat any cut or blister aggressively (I don't mean shout at it). I got a blister last year and went into a tailspin - silly I know but I did - so I went to Boots and asked the pharmacist to tell me what to do. He got me to use Savlon cream on it and keep it covered so that it didn't dry out too much - he said it was best to keep it a bit moist - and to stop any other bacteria getting in. The thing about the feet is, over time, a diabetic's bad circulation can
potentially make it hard for you to notice you've hurt your foot, hence the foot checking, plus your feet have more bacteria so you can
potentially end up infected quite quickly and then of course bacteria feed off sugar, diabetics can heal slower, and an infection sends your sugars up, so there's
potentially a bit of a vicious circle that can arise. You must be years and years and years away from any of that I reckon, if it happens at all.
HOWEVER - the good news is, if you keep yourself fit doing cardiovascular exercise, you get your feet checked yearly at your annual review (they'll use a tuning fork on you, tickle your feet and check the pulse to your feet), and if you keep your feet clean and moisturised then there isn't going to be a problem. Also you are much less likely to have any problems as a result of a cut etc if your sugars are well controlled and these days, diabetic footcare is insanely good at the right hospitals.
As for my blister, nothing happened, it went away as quickly as all the other blisters in my life went away, I kept my leg and felt a bit of a ninny about the tailspin in Boots
but I bought expensive, soft, plush carpets to replace the floorboards that had nails sticking out of them so that I can peacefully and joyfully enjoy walking barefoot around my own home!! I'm a bit of a panicker like you but honestly, don't worry about it, just make sure if you do get a cut or something, don't leave it, do something about it.