Not much info. Why is there increased pressure?? Well, city water, pressure regulator in the system?? Pressure does not have anything to do with temp. A thermostat only looks at temp. But pressure can definitely affect temps at pressure balanced fixtures, like showers.
All day or just for a minute when the first person turned on a faucet or shower?
The good conscientious technician or serviceperson will carry extra oils and lubricants in case the new pump did not come with oil or the oil was accidentally spilled, so the service call can be completed without an extra visit.