I think the term fetish is loosely used sometimes. My understanding is that a fetish is something that may become necessary for sexual fulfillment. That is a definition I read somewhere. That does not apply to me. I don't need feet to be sexually fulfilled each time. But I guess it depends on the definition you read.
You said you can see feet and think that they're so hot that they need to be tickled... I'd say you have a foot fetish.