Stool dropped on top of foot, instant bruise. can walk fine but very painful to touch. when should i get checked out?

Tomorrow?: Get an x-ray.....Find out if you have a fracture. Treatments would include ice for the first 24-48 hours. After that, warm compresses. A surgical shoe is helpful as the foot does not bend in it and this is helpful for healing. Antiinflammatories can help as well. Like alleve or motrin.

Hard to say?: If one is able to walk after this type of injury, and there is bruising and swelling, usually one can determine after elevating the extremity, placing ice on it, and perhaps taking some ibuprofen, that they would be able to tell if they need to be seen or not. If there is any chance of deformity of the foot, one would definitely need to be seen in a few hours to a day or so.

Ice and elevate: If area swells severely or fails to improve after several days have it checked out. Some times a hematoma can develop under skin from excessive bleeding from damage to blood vessels. If it gets worse before that see physician.

Possibly: It could have just ruptured one of the superficial veins in the area, causing an "instant bruise." if it gets worse, see a podiatrist to see if there was any more significant damage.

When you want : To find out what's wrong. An x- ray is really the way to find out if you possibly broke or fractured any bones. You may just have a contusion. If your not in great pain you can delay your visit.