I likely feel that I have the same problem. But when I went to see my Dr. he said I have been through many test (EKG, blood work..) evrything came out negative. The dull pain it is still on day by day at my left chest and under my armpit, it made me uncomfortable. If anyone had the same symptom, please give me some advices. I know that if I go to ER they won't help because I tried it already.
I've seen a doctor after the accident but he did not require me to have a chest x-ray.
If you didn't see a Dr. after or since the accident I would definitely see one now. Sounds like something you don't want to put off (better to know what's going on then worrying. Good luck.