What Causes Discomfort In The Arm?

I am a 32 year old female. For the last 3 days I have been having a strange feeling in my right arm. I can't really explain how it feels. The best thing that I can say is that there are no pins and needles and it doesn't feel numb. It feels uncomfortable no matter what position it is in. I thought at first that I might have slept strangely however it has gone on for a longer time than I would have expected.