Are you using the latest version of XOOPS? If not try to upgrade and see if that fixes it. Also check your templates_c, cache and uploads map for unknown files and delete if necessary...
Personally I don't think you are hacked because your site still works just fine .
@McNaz: I think I will have to learn to type faster
Neo: What vase?
[Neo turns to look for a vase, and as he does, he knocks over a vase of flowers, which shatters on the floor.]
Oracle: That vase.
Neo:...