its a difficult call, you might feel the label is uninterested but there's no harm in checking the situation by sending them a polite email. No label on the planet gets angry when a potential artist asks a question about the status of a release, do bear in mind though that repeated emails can be annoying if something has already been explained.
Really just keep things formal but friendly and remember that a lot of labels depending on their size and status may be extraordinarily busy.
So let's say a week is acceptable in my mind under these circumstances. The label should let you know some info on their idea for your tracks release possibly talking about mastering / artwork / roster schedule depending on what they're plans are.
So just fire them over an email, if you get no reply within a week, then send another since he could be on holiday and needs to catch up. Don't send them daily though that's annoying... and as I say polite and friendly.