Naps & Unsettled

I have a 9 week old Boy (10w on Sunday), who is refusing to nap or sleep past 5pm. He used to nap for 3-4 hours and be a really content baby, had his jabs last Monday, and since then has been super unsettled, and goes from 0-100 in seconds. He now sleeps for 45mins-1.5 hours at a time and wakes up like he’s in discomfort. The only thing that calms him is a bath, but he has really dry skin so Dr said to only bath every other day. It doesn’t seem to be wind as he isn’t doing the signs, and burps after each feed etc. He is pooing normally, and drinking normally. The only other thing I can think of is he is now 99% formula fed due to forgetting to pump (it was 50/50 before). Any help would be great, or reassurance that others are experiencing the same (I didn’t think sleep regression started this early). I am going to try 5 naps, instead of 4, and hop that the extra 45mins-1.5hour help in some way?