1998 Toyota Camry Temperature Gauge Increases Immediately

When I turn on my car, my temperature gauge immediately jumps to halfway, even though it's 50F outside. It will then slowly move up to about 3/4 of the way to the red. The coolant is full, I tried "burping" it, but nothing happened. The radiator fan(s) doesn't seem to be coming on, even though it's heating up. The temperature is the same while idling or at speed. The heat works inside my car. I'd greatly appreciate some input. Thank you!