I was 17 the first time I projected, and after a few minutes, realized what was actually happening and then panic washed over me which caused the quick return to the body..Fear definitely shuts the event fast..
I remember when it began I noticed the digital clock in my room read 2:15AM but didn't care much then what time it was, I roamed around the house and found myself in the dining room and saw the newspaper on the table and noticed that I could see the text very clearly, and also everything else was easy to see and depth perception was extremely enhanced..
This being able to see so good was what surprised me into the realization that I was astral projecting, and that was when I became afraid because I was always taught that astral projection wasn't good..
Upon becoming so fearful of what was happening, I heard a voice say don't be afraid, which made me really panic
.. I then automatically went
back to my body in my bedroom, and noticed travelling there was linear.. Upon reintegration, I sat bolt upright, and got up and saw the time was now 2:25am, I went downstairs to the dining room and saw that the newspaper was right where I saw it while projecting..I just wanted to confirm what really happened.. Since then, I have never astral projected again, but have felt it begin, but now every time it "tries" to happen, something grabs my astral body and pins me to the floor with great strength just holding me there.. I have always been able to wrench free mentally after a few seconds.. I then immediately wake up..
Just to note, I have never tried to AP, and have never actually desired to do it..

