It's not overheating until it gets into the red zone all the way over to the right. The guage is not linear, so the difference between M and L may only be a couple of degrees, while N is 50 degrees away. Dunno the exact numbers, just an example.
You don't need to be worried until the needle hits that red zone. If it's in the L you're fine and that's completely normal for a Ford four cylinder (my 91 Escort ran around the same place).
