Pain in the rib. Happening to my body?

I have a pain in one of the lower ribs (where rib meets the breastbone mainly) on my right side for a few weeks now. The tenderness/pain stays for a day or two and then disappears after some good rest only to come back a few days or weeks later. Pain is not unbearable but hurts more with activities like coughing, laughing, and while trying to sleep on the right side. Last year, I suffered from this similar issue for over 1.5 months after which it all became normal after some treatment and rest. Ever since then pain has come n gone a few time with much lesser intensity. But has now been coming and going frequently for past few weeks. Can anyone help me understand what is happening to my body? I haven't had any recent accidents or injury to cause the pain.