Hi, Welcome to health care magic, I have read your query and understand your concern. As you have mentioned you have pain in your left clavicle region which is likely here to be musculo-skeletal origin since you had history of over head stunt. The initial treatments for all these are, 1. Avoid repetitive overhead activities 2. Do not carry any heavy object or bag on affected (left) shoulder or arm. 3. Apply ice packs for about 15 minutes twice or thrice daily. 4. Apply diclofenac based topical ointment which is more effective than paracetamol based.(available over the counter) 5. Can take oral pain killers if pain is very severe. If still pain is persisting then proper examination of shoulder joint is required to find the exact cause X-ray scan or MRI should be done. You can consult nearby doctor or orthopedician who can write respective scan of the shoulder after taking complete history and thoroughly clinical examination. Hope this information will help you. Regards.