When He Needs Me Most

I'm a trans man in my 20s who recently started exploring a DDLG dynamic as Mommy. It's been challenging but fulfilling, taking care of him and guiding his growth. The other night, he had a panic attack and I was there to comfort him until he fell asleep. But after that, I felt an overwhelming sense of loneliness. Did this mean I failed as a caretaker? Is it normal for me to feel this way when trying so hard to be supportive yet still feeling alone? What should I do?