I fell in my front yard a little bit ago and my foot bent backwards. When I fell I heard a loud crack and I can't bear weight on it. If I lift my foot it feels really heavy and I can only walk if I keep the leg stretched out in front of me. It's not swollen though and no bruising. I have a constant burning pain but don't know if it's just a bad sprain or what?

Yes go get it checked. Even if it is not broke or dislocated you should still get an x-ray and they can recommend a boot or split and meds until it heals.

Yes, it needs to be checked

You need to go for the test before its too late,, according to your question it seems it is not brook,, but you need to check it out...