From your description, you are probably right that your heel is not fractured, however if you develop severe pain or swelling, that is definitely a possibility. I recommend being evaluated by a physician. The most common way the heel gets fractured is by falling from a height, sort of similar to what you are describing. In addition, you don't mention your age or sex but if you have low bone denisty (older, woman) you make have more of a propensity to break your bones. So, if there is any swelling, deformity, or severe pain, I would recommend you see a physician in person so that they can do an exam. A number of other things can cause heel pain, including an ankle sprain, inflammation of the tendons, inflammation of soft tissues in the heel, or bony spurs. Sometimes, these things are brewing and then something like a fall can make it worse or make it more noticeable. Finally, it could also just be normal internal bruising from a fall, even if you don't see the typical "bruise
"- which are unlikely on the bottom of the foot (as the kind of skin you have over the bottom of the foot is different than over the top, so it doesn't show a bruise in the same way). In general, for heel pain, the recommendation is to rest it (refrain from physical activity with repetitive motion like running, jumping or dancing) for1-2 weeks, put ice on the area, and you can take an anti-inflammatory for pain, such as ibuprofen (advil, aleve). However, if you have any reasons not take NSAIDs (stomach problems, bleeding
problems, other medicaitons that might interfere), make sure to check with your doctor
before you take them. As always, it is always better, especially if your pain doesn't improve, to see a doctor in person so they can evalute you.