Why's my gauge cluster all messed up?

[Venom351R]

I have a 2000 Ford Ranger 4x4 Extended cab. The gauge cluster is all screwed up. My oil pressure does not register until after about 10 mins of driving, my gas level only goes as high as 1/4 of a tank from full and recently the water temp gauge has become stuck. First it was stuck half way between the C and the H it would not go down even after the truck sat all night when I went to leave in the morning it would still be at half way and now its stuck at straight up almost on the H. I dont belive its over heating its never had that issue I just think the gauge is screwed up. Any idea's on whats causing this and how to fix it. I dont care as much about the other ones as much as the water temp one