Cant switch weapons at all- stuck with Pistol

[5persondude]

i just started playing this game a few days ago, and for some reason after i talk with the brother at the docks, none of the invenotry actions work at all-

i cant select another weapon, even if i roll the middle mouse ball up/down or try the number keys at the top
I cant drop the handgun cuz clicking the middle mouse button doesnt work even though its assigned to the middle mouse button

this happens at pure random when i start a new game- sometimes i get it to work right, but most of the time it totally ♥♥♥♥♥ up and nothing will work

[PolaricEntropy]

See this thread http://steamcommunity.com/app/6910/discussions/0/540731691530594839/