Answer by  
                                                                                          Dixie (60)
                                                            
                          
                          
                                                          you possible have a pulled ligament and or muscle strain Try heating a damp towel in a microwave and place on the affected area you may be able to relieve some tension in the area. You should see a Dr. concerning the difficulty straightening the leg as you could be having patella slipping or dislocation as well.