Residential HVAC (Heat Pump) question

Could be a number of things or a combination of things. You already can tell the service technician more than most homeowners. Just as a dummy check, make sure you have a clean filter at the air handler. Refrigerant pressures are a function of airflow across the coils, ambient temps, condition of the refrigerant line components, and level of available refrigerant. Filter is probably not the issue, but its a cheap fix and the tech will hit you up for it ($$$) if it needs replacement.

To build on what JDMopar said, heat pumps usually produce air cooler than your body temp, so they won't feel hot like conditioned air produced by a gas furnace or your electric heat strips. Although some modern high efficiency heat pumps are cranking over 100F...