My electric heater gets to temp but the fan continues running. My thermostat says the fan is off. No idea when I'll be able to get an actual HVAC person to my house, due to the current state of affairs in Texas so I'm trying to troubleshoot this myself so it doesn't happen overnight.

Make sure the fan on/auto switch on your thermostat is set to auto. If it is set to auto, then Take your thermostat off of the wall, remove the G wire (should be green), see if the fan shuts off, if the fan stops running you need a new wall thermostat. If it does not shut off after removing the green wire for the thermostat, it is most likely the control board on the air handler.

Many of the air handlers have a fan delay relay. Every once in a while they will stick closed. Go to your air handler and tap on the side of it. Make sure the unit is not calling for heat and the thermostat is in the auto position for the fan. Many times this will jar the relay and it will work. Eventually you will need to replace it.

Check your filter - might be reducing the airflow causing the high heat sensor to trip

Well, good that the fan runs. If the thermostat indicates fan operation ( digital display ), and it is not indicating "Fan" I say the thermostat is not commanding the fan to be on. Electric heat typically has a sequencer that commands the fan on with the call for heat. This sequencer may be the issue. Also, some may have a temperature limit that may of tripped and will keep the fan on. I'd be reluctant to mess with something that may keep the fan from operating. No fan = No heat.
Best wishes for everyone dealing with the temperature extremes.

In order to properly troubleshoot mechanical failures, one must first know what we're working on...

Make, model and serial would be of great help.