I am not a medical doctor, but if you are in extreme pain and cannot put weight on your injured foot it sounds like you should go to an emergency room: you may have broken a bone in your foot or injured a ligament. Hopefully not. Take a picture of your scraped knee and any bruising or swelling to your injured foot; take several pictures in fact. Also have someone take pictures of what caused you to fall.
I would recommend your fall is reported promptly to the property manager for your apartment complex because it can create an issue later if there is a delay in reporting. If you are thinking of hiring an attorney though, the safest bet would be to have the attorney notify the apartment complex of the claim. Either way, I would strongly advise against giving a written or recorded statement, either to the apartment complex or their insurance company: they want it for their benefit, not yours.
I've handled quite a few uneven sidewalk cases before. In fact I have two that are in suit right now: one is a badly broken elbow from an uneven sidewalk, the other is a fractured ankle with two surgeries: again due to an uneven sidewalk. I also settled a broken foot claim about two months ago for a lady in Galveston: that was an uneven parking lot at an apartment complex where she worked.
Seeing pictures would help a lot, but to have a successful claim you need to establish that the condition that caused you to trip is an "unreasonably dangerous" condition, and the apartment complex either: (a) created the condition themselves; (b) knew about the condition before you fell, yet did nothing to warn you of it or fix it; or (c) the condition had existed long enough that, through a reasonable inspection, the apartment complex should have found it, fixed it or warned you of it.
Hope that helps. Trip-and-fall claims are a lot trickier than car accidents because the law makes a trip-and-fall claim harder to prove. This isn't a sales pitch, but you would fare better with a good attorney helping you from the get go.
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