Sleeping issue 8 months old

After some advice as I never had this with my girls .

From Peadar-James turned 7 months hes been finding it hard to sleep . It started as an unsettled night here and there to what we called the Wednesday club where he wakes every hour on the dot and cant settle (only happening on Wednesdays) but it seems to be getting worse the last week has been really hard he falls asleep after his bath and gets put to bed within minutes hes sitting up playing with his teddy and cot bumpers. He'll then let down and then sit up and so on Wednesday night I had to walk about the room with him and he finally fell asleep at midnight last night was similar hes now been thrashing about his cot the last few nights after sleeping for a couple of hours. Hes sitting up lying down going sideways upside down. Gurning whinging crying but hes not wakening up even when thrashing about is causing him to bang his head of the bars of cot. It's like something from the exorcist. Lol has anyone had experience of this or know what could be causing it. I'm starting to think I need to take him to the GP