what happened after we death..?

The Heaven and Hell that you refer to are not physical places, rather they are states of being. When we die, we meet our Maker for the "first time". Probably not really the first time, but the first time in our human memory. If we face up to what we have done to the people that we have touched in our lives and what we have done to the Creator Himself and accept that WE DID THESE THINGS and ask forgiveness, then I believe that we will spend eternity in His presence. This would be "Heaven". If we harden our hearts and will not acknowledge our indiscretions and will not ask forgiveness and turn our backs on the Creator, we will spend eternity outside of His presence. This would be "Hell".

No one knows what happens after we die. Most of the worlds religions were founded in part to answer this question. They offer their interpretations and use the idea of a heaven and hell to control the behavior of their followers. The sad truth is that none of them have the answer, only the mythology they have developed to promote their own brand of religion. The only true answer to your question is that no one knows the answer and any one who tells you that they have the definitive answer is a liar.

I believe that our physical body is a vehicle or a vessel that we wear for a little while to learn some necessary lessons here on earth. When the classes are done and the terms are over, we go back to our true home.

I believe this is one the greatest questions in life, "where will we go after we die"? the other one is that "where did we came from before we exist in this life?" and "what is our Purpose why we are here?" and what we mean when we say Heaven? and what is Hell? these are very interesting questions we have in mind. I am very pleased to help you on this matter, here is a link to answer all your questions http://mormon.org/plan-of-happiness/