First you need to take a couple of pain killers (ibuprofren is best for this). The best thing that I you can do for it is use some activated charcoal (you can find it at just about every health/drug store). Second to this would be to take a cigarette break it in half, and then hold the tobacco from inside of the cigarette onto the sting. (I've found that it is easiest to just take a handful of tobacco and use a band-aid to hold it on. This is one of those little known but always works type of things I hope it helps.
Besides taking the ibuprofin and benedril, also take an unbuffered aspirin and dip the edge of it in some water until it just starts to dissolve and then rub the slightly dissolved asprin over the area on and around the bee sting repeat this until a paste forms.
You can take pain killers and benadryl for itching and swelling. Apply a baking soda+water paste to the sting, or mud as the idea of it is that as the paste dries it pulls the poison out.
I always find that a little bicarbonte of soda mixed with a tablespoon of water helps me.
Sorry to hear about the bee sting. I would make sure you take ibprofen for the pain you can take up to 800 mg every 6-8 hours. After a few hours the pain should not be as bad. If you only have tylenol you can take up to 500-1000 mg every 6-8 hours. Benadryl can help also. You can try ice on the sting. It may swell up to where you can't wear a sock or a shoe for a while that is why you want to take some benadryl to help that out. Make sure the stinger is not still in it. Keep it clean and covered since it is on the bottom of your foot. You can try putting some neosporin on it or an antibiotic cream like bacterin I think they call it you can get at the pharmacy. Also, I have heard baking soda helps a little too. I have never tried that though. Good luck and get feeling better soon. For more advice you can call your local pharmacy, etc. Good luck once again.