The first thing I do when a mechanical gauge is doing something weird is tap the face of the instrument. There have been numerous instances where I have seen a good rap makes the gauge stand up and pay attention
Cessna fuel gauges usually respond well to percussive rectification. I'm one of those oddballs that includes the engine dials in my scan and I can't say I've ever noticed any fuel pressure weirdness. I don't know what you are flying but I fly the 161 version. I would always suspect a dial problem first although obviously having said that if it was fuel, oil pressure or temp then get on the ground whether you think it's a dial or not and sort it out with your feet on the grass.