I noticed this uncomfortable feeling of something in my back. This appeared about 3 months ago. I noticed it sleeping on my back and in my car/seat while driving. This is different from the left side. Its a HARD not painful or not sore but a lump in my lower right back just under my last rib. I am VERY aware of my body and it is something new. Is there an additional rib on the lower right side, kind of under or deeper and shorter in? ABOUT ME- I am a healthy 41 year old male, No smoke, drink rarely/socially only. I run 30 miles a week. I feel and look alot younger than my age. Thank you for the advice, Dean Bosman, Long Beach, California.