Yes this is a phase and yes it will pass I promise. Often they will practice the rolling, learning to crawl in thier sleep in the cots and consequently wake themselves up. Add to this he could be teething and you end up with all nighters.

I remember when DS's first tooth was coming through we went through nights of him waking every 30 - 45 mins, at least a day of non-stop crying/grizzling with seeming no explanation. When I was almost at the end of my tether I took him for a walk and happened to stick my fingers in his mouth just to check and lo and behold we had a tooth... I don't think I have ever been so happy at that point in time

Sometimes food can make them really unsettled too... did the unsettledness overnight seem to coincide with when you started solids?

I know many people believe at this age they only feed for comfort and I am sure that is a part of it but I know with my DS he would often feed for longer at night so I knew for him it was about the food not just the comfort. I also wonder with this heat if he is thirsty as well which could be contributing to why he is waking.

The only way I survived was to co-sleep, I would sleep with him through the day when I had the chance and found he slept for longer when I did

you are doing such a great job and sleep deprivation has to be the worst