God truly saved me at some point in there. I don't know when, but I do know that I wanted to know Jesus Christ as Lord and Saviour. I walked the aisle in that church because I loved Jesus Christ. I loved the Lord, because at some point before my heart had been changed by the Holy Spirit.
There are countless Christians who have affirmed they are saved by walking and aisle and praying a prayer. But doing that saves no one. It is the work of the Holy Spirit.
The walk down the aisle motif of modern evangelical Christianity is based on misguided, revivalist thinking. But many Christians today associate it with salvation. However, the alter call is an invention of 19th century revivalism, that has (IMHO) serious theological problems. Still God has used it despite its theological flaws. Of course such flaws, though used by God, also bring error in thier wake as well.
It is like early Medieval monasticism. Monasticism is not biblical and has some theological problems as well, but God used this flawed system to convert Europe to the Gospel and to preserve the Scriptures for us today. This monasticism did great good, and on the other hand, was the breeding ground for great error.
Remember, even in our errors and sins, God will accomplish His will. We are responsible before Him for our errors, but thankfully He is God and none of our frailties (or sins) can thwart His plan and all of them are used to accomplish all His most Holy Will.