I just do not know what to do!

Elizabeth
My LO was EBF for 8 weeks. Then to pumped milk in a bottle when I went to work. He had been doing ok, taking 2-3 oz 3x a day. I posted a bit ago about him swapping day/night feeding schedule. I tried reducing night feeds and it seemed to help some last week. Now today, he did not eat at all from 7 until 4. He nursed at 7 before we left for the day, and 4 when I picked him up. What can I do?! We have a dr apt tomorrow, but wanted to know what other mamas have done.