It sounds like you might have a couple of things going on---one is the possibility of an infection from either the extraction or another tooth in the area. I think you need to be seen with the possibility of needing antibiotics. The second is trismus which can be caused by the infection and or the injection into the muscles in that area.I would suggest you get some tongue blades and every day add one or how many you can to stretch those muscles. For sure there will be discomfort when you do this but it is important that you break the adhesions in the muscles.