My low pressure oil light keeps coming on when i stop and i just got my oil changed. The oil is not low. What could be the problem?

When you say the "oil light," do you mean the light that says "Change oil" or are you seeing the red light that indicates low oil pressure?

If you're seeing that red light, that likely means you have low oil pressure and should stop driving immediately, until the problem is diagnosed and repaired.

It's also possible to see the oil pressure light on when there's no issue with oil pressure, if the oil pressure sender has failed or there's a connection problem.

If the oil light you're referring to is the "change oil" light, you will need to manually reset it for it to disappear. Here's how (from Chrysler):

1. Turn the ignition switch to the ON/RUN position (do not start the engine).
2. Fully depress the accelerator pedal, slowly, three times within 10 seconds.
3. Turn the ignition switch to the OFF/LOCK position.
NOTE: If the indicator message illuminates when you start the engine, the oil change indicator system did not reset. If necessary, repeat these steps.

You need to find out why you have low oil pressure. It is normal that as engine rpm's increase, the oil pressure will rise- the oil pump is moving oil faster. Even though your light goes out, you could still have critically low oil pressure. There should be sufficient pressure at idle to keep the light off. The light will come on when your oil pressure is almost nil- I believe for some it's as low as 8 psi. Normally, oil pressure at idle is specified anywhere from 15 to 40 psi. You would have to check specifications for your Expedition. To verify oil pressure, hook up a mechanical gauge at the oil pressure sending unit on the engine block. Check with a local shop.

The causes run from easy, simple to budget busting ruin. Low oil level, wrong grade oil, real old oil, oil leaks, internal oil leaks, worn oil pump, worn crankshaft bearings. It was pretty common on older very high mileage cars to have a fluttering oil light at stops and idle. It was time for a rebuild, or time to look for another car.

anything less than 15 psi is low... and this is for all automotive engines

The oil light is for low oil pressure, not low oil.
You need to have someone check the actual oil pressure with a mechanical gauge or change the oil pressure switch and see it the light still comes on.

This may mean engine wear or bad oil pump. I would have the oil pressure tested to see if its a shot some where or if the pressure is really low, this is done by removing the sensor and installing a gauge and driving the car to see if the pressure is low, if the pressure is low then more checking is neede to see why,you may have worn engine bearings or bad oil pump. depending on the mileage it may be smarter to replace the engine, not knowing what internal damage has been done already. good day.

the oil light is coming on due to sensed low engine oil pressure, this is not a level issue unless u are about 3 quarts low, oil pressure indicators don't leave any computer codes, so who ever told u that is wrong, u need to test the oil pressure with a mechanical gage when the oil light is on, until U need to confirm that u don't have a real pressure issue here or you can burn out the engine bearings, if the pressure checks ok then rplace the oil pressure light sending unit in the engine.

did you change the screen with the oil pump?
sometimes the screen will get clogged up and lose oil pressure.

Take a gauge and check you oil pressure. If its not low then change the pressure sensor. If the pressure varies and the pressure is not where it is supposed to be, then drop the oil pan and look in the bottom of the pan. If you see slivers of metal then the bearings are going out. Eather the cam bearing, rod bearing, or main bearings.

check if there is too much oil. over filling the engine with oil causes the oil to foam which leads to loss of oil pressure. it could also be the oil pressure sensor

This is the pressure light, nothing to do with the oil needing to be being changed, you have low oil pressure being indicated, this will destroy the engine if the light is really indicating low oil pressure, have the oil pressure tested with a mechanical test guage at a shop, if the oil pressure is ok then replace the oil pressure light sending unit.