Check ur fluid level if u havent yet.

If its white and bubbling or really low then try just topping it up. If you top it up, monitor it over the next little bit, every couple days to start. If its just the fluid dropping then u got a leak, but if it stays the same then u got pump problems.

If the level is not down then check your belt tension, if your belt hasd stretched then it may just be that the power from the engine is being connected with the pump and not working right because of lack in power.