New Hamster won't come out/ house as restroom?

[Toto]

Hey... I got my first hamster yesterday and understand that I have to be patient but he won't leave his house. I don't want to bother him and I do want to let him get used to his new environment. However he has been using his house as a restroom. I'm really nervous!!

I heard that its bad for him to sleep in the same area he used to go to the restroom... and I don't want him to develop any health issues.

How long should I wait to interfere? Will he learn to go to the restroom elsewhere??