That actually sounds pretty believable...I tried using grenades (They are my choice of weapon) and I would never hear them go off, which was really strange. It would never hurt any opponent, and I would end up being killed over and over again because my grenades didn't take damage.
But everything else seems to work fine. Occasionally the SAW along with the assault rifle wouldn't work at all, as in if you right-clicked with it no bullets shot out, and the number on your XP bar would never go down. And also sometimes if it did, no bullets shot out.
But Dblo, don't stress on working on something if it half-works, fix whatever doesn't work at all. The SAW can wait, it's pretty functional for now.
I can't believe you worked for 18 hours yesterday. Take care of yourself, kay? :)