I think that is a tough question to answer because you don't know until you know. I may be wrong, but I think some sort of diagnostic test (bone scan, MRI) has to be done in order to confirm there is a SF.
From my personal experience, I had a SF in my femur a few years ago. If I ran 2-3 days in a row or if I did a hard run, pain would be bad enough to make walking very difficult for a day or so after. Also, had pain while cycling and even just walking at times. Finally, I would have pain just sitting around. Not constant, though. Would come on unexpectedly and last maybe 5-15 minutes. I can't really remember how often this happened. Maybe a couple times a day, but it easily could have been every couple days. Hard to really describe the pain, but I think I explained to my doc that it felt like my bone was being put through a meat grinder.
Hope that helps and hope you don't have a SF.
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