Is my tooth filling loose or leaking or normal?

I had a zinc amalgam filling removed last month cause it became loose and i replace it with a silver filling, is it possible for it to be loose or leaking this early???? There is no pain or sensitivity to cold liquids and foods, and even i can chew hard substances, i want to how to find whether it is loose or leaking, and if it is loose or leaking what would the dentist do???