What a bittersweet moment, you described it so beautifully, thank you for sharing. You must be so proud of your daughter!
I still remember my first days away at college. My dad went out to CA with me to help me get settled and I was so embarrassed he kept wanting to hang out with me. I'm like, "Da-ad! Why don't you go to the parent events!" Sheesh! How can I fit in with the other students when my dorky dad keeps hanging around me?
Then on the day he left we said goodbye and I closed my dorm room door. I forgot to ask or tell him something (I don't remember what, but it was something minor) so I opened the door again as he was turning away and I could see tears in my eyes. That touched me, even 18 year old me. My dad passed away from cancer while I was in medical school and I still miss him. I'm sure I'll be bawling when my daughter goes off to college.
Hope your daughter's first days go smoothly and good luck to you with the adjustment!