Diamond Loose

Hi Ladies,

I've only been engaged for about 2 months and tonight I accidentally hit my ring on the table and I think the diamond might be loose!! I'm not definitely sure, but when I tried to put my finger on it, I believe it moved slightly and when I put it up to my ear I can hear a slight rattling sound. This MIGHT be how it has been all along and I can't see any dents or scratches.

What should I do? I am very nervous because the diamond was my grandmother's that she left me when she passed away and it's irreplaceable, however the ring is insured.

Do you think it's loose or just my imagination? Should I bring it to my jeweler this weekend to have them take a look and try to tighten it?

Thoughts? Thanks!