1. I am guilty of biting my fingernails when stressed, to the point my fingers become stumpy and the ends are sore.

I visited a 7/11 this evening and forgot to use hand sanitizer after opening one of the fridge doors. I later went to the gym and used dumbbells etc. 

In both occasions, I was touching my thumb nail as it was sore from how far I had bitten down my nail.

2. I frequently get athletes foot due to wearing sneakers or boots for work. One evening I noticed my sock was very bloody, and after taking it off noticed that the skin had split between two of my toes.

I walked bare feet in a locker room to use the showers.

3. I have just ended a short-term relationship with a girl. We engaged ONLY in deep French / open mouth tongue kissing (sometimes quite vigorous). We never had sex or oral (i.e BJ / fingering).

Would you advise testing on account of any of the above? (i.e supposing there were genital or vaginal fluids / blood that I did not see on the fridge door or locker room floor and walked through it) or am I completely in the clear?

Your opening statement is correct. All by itself, that pretty well answers your numbered questions.

1,2. Nobody ever got HIV from contact with a contaminated environment -- with or without finger biting or exposure of other cuts or wounds. No risk at all from either of these sorts of events.

3. These exposures carried no chance of you being infected with HIV, even if your kissing partner had HIV. And probably she wasn't infected anyway.

You do not need testing for HIV. You are completely in the clear.

I hope these comments are helpful. Let me know if anything isn't clear.

HHH, MD