Listen, girl. There's a mom in my town who used DE as well. We see each other at support groups at times. I saw her and her little boy at the store the other day and was SO jealous that he looks like her, even though I know he's from a donor egg and donor sperm! One of my twins could conceivably look a bit like me. The other...my heavens...he looks Nordic and my DH and I are both dark. No idea where that coloring even came from. I started going through my brain all over again why we chose our donor, maybe I should have waited for someone of my ethnicity, etc. I mean really, we can go to some ugly places if we let ourselves! In the end, yes, there will be little pangs of pain and wonder and sadness, but you know what? That happens no matter what, no matter whose egg or whose sperm or whose uterus. It just happens when you're a parent, period. Boy, did I go through it a few weeks ago when my OE DD started crying because her grandparents are so old (and only one of them is functional as a grandparent and he lives across the country), and 2 of them are dead, and all of her friends have "young" grandparents to go to their b-day parties and she has no one. OMG. I felt so horrible that I waited so long to have her, and that I can't offer her grandparents or an extended family (I'm an only child). The guilt was very profound, but I found myself empathizing with her (my parents were 42 and 53 when I was born and my grandparents were either dead or living in a different country) and then explaining how there are all kinds of families, big and small and in between and that each is special in its own way.
You have to be ready to just let the feelings come and go. It's natural, and part of the challenge of being a parent...no matter whose genes are involved.