I'm confused as to whether it's a sty or a keratosis, so I'm asking.

Lately, I've been feeling like I've developed a callus on the sole of my foot. It feels like a slight prickle every time I walk, and it's uncomfortable. So I looked it up and found out it can be confused with calluses. I'm not sure what it is just by looking at the picture, so I'm asking.

I used to just think it was a callus and ignore it, but now I'm feeling a little pain, so I'm wondering if self-care will solve it. I'm having trouble deciding if I can gently scrape it off, or if I should just leave it alone and go to the hospital.

I'm wondering if I need to have it professionally removed if it's a sty, or if moisturizing and exfoliating are enough if it's keratosis. I'd also like to know at what severity I should seek medical attention.