Reason For Sudden Pain In Shoulder Blades After Waking Up

I woke up with a sudden pain between my shoulder blades, like I may have pulled a muscle. It was fine but the pain was a little much so i tried to take a nap in hopes that it would subside. The pain is greater now and its only been about three hours. The pain comes suddenly and is sort of sharp. I am currently laying down and changing my position does not help much. When i sneeze the pain is there but not as bad as when the sudden pains come along. The rest of my body feels fine but my throat feels like there is something stuck there, like im nervous and choke up, it may just be because i am nervous that this is a bigger issue than just a little back pain though so im not sure if its an actual symptom. I did not have any problem when I went to sleep and it only stared hurting after waking up. My mother doesn't get home for a few hours, but should i go to the emergency room? I've never gone to one and am not sure what this entails. I am a 26 year old female, 189lbs and 5'6. No other health problems but a slight high blood pressure from what i know.