since the smell isnt on you it isnt a health issue per se like infections....
that said ...
mold can grow anywhere, where there is a dampness ...laundry baskets, behind and underneath toilet tanks, under beds, under other furnishings where there is no ventilation. old houses are known to have a mustly, moldy smell due to poor insolation, cracks and crevices that dont get ventilation.

dorm rooms are famous for having what is called locker room spells (musty moldy dirty sock smells)

my suggestion place a book under each of your beds "feet" that will elevate the bed so that ventilation can get under there to dry any cold dampness. do that with any other closed bottom furnishings also. keep your laundry done and wash out the laundry basket every time you do the laundry, use the bathroom fan when taking baths and showers as this will draw out the moisture in that room to prevent mold growing in cracks crevices and behind the toilet. when you do take showers baths hang the towel high over the bathroom door that way the heat will dry it faster. (mold can grow on damp towels too) wash your bedding (sheets and blankets and pillow cases) at least once a week even if you dont think it needs it, (this will also cut down on cross contamination odors and such from your room mates sitting on your bed)

febreeze is a spray on that can also deodorize and freshen up things.

and know that in dorms the problem may seem like its you but it could very well be a room mates problem. in that case theres nothing you can do.