Since cold air sinks to the floor by itself and your outlets are already at floor level, you're getting very little mixing due to natural convection and this is making your AC unit ineffective at cooling your room (as you've figured out).
Buy or make a deflector to put over the vents on the AC unit to direct the air up into the room. This way the cold air will be directed up, directly cooling more of the air that your body occupies, and, as it naturally sinks due to convection it will mix with warmer air making more of the room more comfortable.
This is an example of a commonly produced vent deflector that I'm thinking about:

Images courtesy of lowes.com. No endorsement intended or implied
If you have a larger outlet vent on your AC unit, a deflector like this (designed for placing over a ceiling mounted vent and directing the cold air away from one person's desk) may work better (direct the air up):

If neither of these will work for your particular unit, you may have to get creative with cardboard to design a deflector that works for you. If you don't like the look of cardboard, you could use it as a template to bend a sheet of thin plastic (it's amazing what you can do with a couple of blocks of wood and a hair dryer or heat gun) to replace it. Glue a couple of magnets to the plastic and use those to hold it to the AC unit, or, possibly, drill holes, remove the default grill, and use those to mount your new deflector directly to the AC unit.