DD slept til 4am- not sure this is a good thing

kmhunt11

I've been having supply problems in the evenings. More than enough milk in the morning but literally none by 7pm. Last nigt she nursed at 6:30-7 and I pumped. At 8ish. I gave her a bottle of expressed milk at 9:30. She didn't take an abnormal amount but she slept from 10:30-4. She's only 5 weeks and I've never had to wake her to eat- she's usually like clockwork. She's gained plenty of weight- 8lb at birth, 8lb11 3 weeks ago, 9lb10 yesterday. Is almost 6 hrs at night too long for 5 weeks?  My other concern is she only took one side at 4am and I didn't wake up this morning engorged at all. My right breast went from 8:30- 7am without any nursing or pumping and it merely felt full....