Thanks for your question on Healthcare Magic.
I can understand your concern.
Since your ecg and chest
x ray are normal, no need to worry for major heart or lung related diseases.
Possibility of
costochondritis is more.
It is inflammation of costal
cartilage. You are also feeling some swelling of chest wall. This is also seen in costochondritis.
So better to follow these steps for quick recovery.
1. Avoid movements causing pain.
2. Avoid heavyweight lifting and strenuous exercise.
3. Avoid bad postures in sleep.
4. Apply warm water pad on affected areas.
5. Take painkiller and anti inflammatory drugs.
Don't worry, you will be alright.
Hope I have solved your query. I will be happy to help you further. Wish you good health. Thanks.