I'm so sorry you're feeling this way, Marcy. You are definitely not alone. Our boys are 1-1/2 years apart, and our daughter is 6-1/2 years older. It was a very stressful time. A friend said that our boys were like puppies, and being a bit of an older mom, I was overwhelmed (add in all the other life stressors and it was a recipe for disaster)! I stopped scrapping. My daughter has albums up until the boys were born. I saved everything, but didn't scrapbook any of it. AND in one of our moves, all of the kids' early school papers, drawings, etc, got lost.
So... all of this to say, I am in the same boat. I look at some photos, and I don't remember why I took them. But, I scrap them because I have them. Sometimes the kids will remember things. Sometimes they're just cute photos. They're in the scrapbook and that's a good thing, right?
Big hugs to you. I hope that your overwhelm diminishes and your memory returns!