This is so strange. On my left hip it feels like there is a bruise, and is very tender when I touch it - almost like a burning sensation, but there is nothing there! I can feel it when pulling on pants, shorts, etc. Just started noticing it yesterday. My boyfriend looks at me like I'm crazy because there is no bump or bruise or anything, but its sore! What could this be??
I don't know what it could be but, try putting an ice pack on it for about 10 or 20 minutes. If it is a little bit of inflammation from something (although I can't think of what when you can't find a bump or anything) ice may put an end to it.
My best advice would be to go to a doctor to make sure he or she doesn't know what it is based just on your description. Plus, when we can't see anything, they might with a trained eye. Or, with a trained ear as what we tell doctors sometimes tells them alot.