His little toe is very swollen, red and painful. he works outdoors in the cold but can't remember banging it at any time to cause injury. ?

Need exam: This can be from a variety of conditions. Will need exam to give accurate DX

Inflammation....: You have described the cardinal signs of classic inflammation. Not necessarily an infection, but certainly inflamed. All flannel aside, the toe needs to be examined. Sooner is always better than later, just in case a easy treatment can end the problem quickly.

It may be: an infection. get an X-ray and see a dr.