I have some "memories" that have definitely been created by looking at pictures later. I actually remember one particular case where it was a photo of me as an infant in my mother's arms and I told my siblings that I remembered that and that I was sucking on a biscuit (which you couldn't see on that photo). It turned out that there was another photo of the same time where you could see that I was indeed sucking on a biscuit. That "memory" had been created.
However I do have plenty of memories from childhood that were not created later by other means. The earliest being for sure around age 3, when I had eye surgery. I remember a few things very clearly of that period. (because it was different and somewhat traumatic for a 3yo) For the most part these were not reactivated later by pictures or recounted as stories. (because people around probably didn't even remember them themselves for being insignificant to them)
E.g. I remember being pushed by a girl behind me in line in kindergarten, my glasses fell on the ground and one lens popped out and I blamed her for it. I was likely around 4 or 5.
I have recently started therapy and we're doing what's called "lifespan integration" (http://www.lifespanintegration.com/) where we go through life events year after a year and where I try to picture each particular moment to feel like I'm there. One interesting effect is that more memories besides the initial ones written down have come back over time or some come back with more details. I would think that or other techniques (e.g. hypnosis) could help you remember more things.