nursemeg...I can usually tell that my daughter isn't hungry if I latch her on and she sucks rather weakly. She just kinda hangs out there and doesn't change her suck throughout the feed.
If she's genuinely hungry, then her suck is fast and quick ..like we are when we're starving, yk? We kind of just stuff our mouth and try to get it quickly into our stomachs!
Does that help? I'm sorry I can't provide anything more concrete for you.
I really don't think you should worry about the night feed. It's only 1
My baby was feeding once in the night and she was 7 months. I knew she could sleep through the night bc she's been doing it since 2 and half months. Once they know how to do it, they don't usually 'forget'. It's a developmental thing, I believe. I genuinely know that when my baby wakes at night, there's something up. If it's not cold, pain, hot..then I let her feed for just a couple of minutes and then she falls right back to sleep. Sometimes that's a good clue..if they just fall right back to sleep after a feed