Can I lose my salvation. What about in 2 Timothy 2:12 where is says that If we deny Him, He also deny us. Does that mean that if I deny my Lord I will go to hell. What about Peter who denied the Lord but wasn't damned. What does this verse mean?

Certainly as you say we can because of ignorance, neglect or sin, and the denial of God's principles in our lives, "lose our salvation" at the judgement seat, when if we are rejected, God will deny us, and we will be denied an entry into that great and glorious kingdom on earth, long promised for all the faithful saints.

Your contrast of the quotation of 2 Timothy 2:12 and the occasion where Peter denied his Lord three times is interesting and very relevant to our own lives. It shows firstly that there is a difference between the two denials. In Timothy I believe we are being warned of a TOTAL denial, ie. disbelief in our hearts of the greatness and goodness of God so that our total faith and trust in Him has been swept away - this is a tragedy in a man or womans life.

Secondly in the case of Peter, the element of forgiveness is introduced, and even although he, under great stress, perhaps greater than we will ever meet, certainly did through fear and lapse of trust deny his Lord, that same Lord was able to forgive him just as today He can forgive us.