Hello and welcome from the UK!
Your Littlie looks fine from over here!!!!! But if you have any concerns whatsoever, it's best to get your vet to look him over, if only to ease your mind
Oh, and when we got Harry

at 3 months, he was totally black + tan....I know the sun was shining, but have a look at him now....

. They do keep changing colour, and apart from hair-dye, there's not much we can do about it!
Congratulations, and look forward to getting to know you. Sally + Harry x