Spot on foot

[paddymayday]

Hi, my ds has a little spot on the soul of his foot which looks almost like a pimple/blister. He is complaining that it hurts to walk on, but seems better when he has shoes on. Its not itchy. I wasn't sure if he has something in it or it is a dreaded wart! I have an appt at the drs later today but just wondered if anyone has any ideas?
Can warts/verrucas hurt?
Thanks in advance :-)

How longs he has it? Could it be the start of hand foot and mouth?

Thanks for your response. He has had it since the weekend which made me think he had trodden on something in the garden but then it wasn't an immediate "ouch" so maybe not.
He is otherwise well in himself and no spots anywhere else so don't think it's HF&M. Deep down I think it's a wart but hoping against hope its not as I am currently seeing a podiatrist to get rid of mine and the treatment blooming hurts! (I am very careful with always having mine covered not sharing towels etc so would be very bad luck if he now has one!)
I will let you know what the drs say this afternoon.