Firstly, I don't think you have made a mistake with the dummy - there's tons of research out there that suggests that dummies are really good for babies (including findings that dummies actually reduce the risk of cotdeath!!!) and Tracy herself said that there was nothing wrong with using a dummy (although it does sound as though it's becoming a prop etc).
My first thought would be - how's the temperature in the room? It's quite easy for a baby to be uncomfortably hot/cold in a room that feels ok to us - have you got a room thermometer? Sophie was sleeping really badly for a few weeks and I figured it was teething as she's just cut her first tooth but we adjusted the heating in her room and now she's sleeping like a baby lol!
It sounds as though he's still pretty young to be hungry - even babies who show signs of needing to be weaned early are usually older than 3 months!
Also, I'd suggest looking into silent reflux - I don't know a lot about it but know that it can cause sleep disturbance. I don't know how that sits though considering how well he's slept until now.
I don't think you should feel bad for complaining - we get used to the sleep we're "allowed" and when that gets disturbed, it's still really exhausting.
On the whole I don't think I've been much help
Hugs honey and hopefully you'll get tons of much more helpful advice. Hope he goes back to his old sleep habits real soon
