@BlueBoy2 for what it’s worth, I think you’ve done the right thing - you’ve had him overnight and an afternoon and he should have toiletted and be drinking normally long before now. Even my best ‘trained’ puppy would have needed to wee and poo by now (Golden Retriever - clean from 10pm-6am from 8 weeks).
And he shouldn’t be timid. A timid puppy is not a good thing. They might jump away from a loud noise (for example) but their overarching instinct should be to explore and be inquisitive. For example if you dropped a bowl next to your puppy, it should jump but then it should go straight into ‘oh what’s that’ mode.
People always forget how resilient a well-bred puppy should be. They want to trust and they want to explore. The world is literally their oyster. They shouldn’t be fearful, even if they’re going home late. Their first fear phase ends at about 12 weeks and starts again at about 6 months - but even during that, a well-bred puppy (not from a puppy farm and well raised), should trust their knew family completely. All a happy and well bred puppy should know is how to trust absolutely.
If you do buy another puppy, please consider coming back here for advice - and please do consider a pedigree. It’s a lot easier to tell a good breeder from a bad one if you go with a pedigree and it’s a lot easier to figure out health testing as it’s so straightforward.
But the most important piece of advice I can afford: don’t blame yourself. These people are the ultimate scam artists and the lowest of the low. Finding a good breeder takes time, patience and a lot of effort - people can wait months or even years for the right litter from the right breeder - and it is easy to make mistakes when you’re new to dog ownership. And it’s easy to get sucked in.