>"I'm a bit worried now, I have all my savings in there. "
I don't see that there is anything to worry about. I thought the answers had said that but clearly you are concerned and probably nothing we say will help make you feel better, but I'll try.
In the very unlikely event anything goes wrong your money will be guaranteed up to the limits (can't remember it now but it's something like £60000. But if Santander were to go 'belly up' (which it certainly won't) then the whole banking system will collapse so money will be worthless.