Motorola

I have a question about the total memory on the V400 phone. Yesterday, when I checked the "total" free space, it said that there was 5069 Kb. When I checked a little later, it now said 4964 Kb of total memory. Is this drop normal?

P.S. I have download a game from the Cingular website and have added a few mp3s and graphics using the Mobile Phone Tools software, if this makes any difference.