Another Sleep Issue

[Georgi]

Since DS first started teething (about 2months ago) his day sleeps have turned to slop!

He was always a great sleeper but something has just happened

He sleeps no problem at night - 7pm to 7am. I put him back to sleep around 9.30am & he only sleeps for 20 - 30mins

I then put him back to sleep around 1.30pm and he again only sleeps for around 30mins

He wakes up crying so I try to re settle him by patting him but he just cries louder & louder until he becomes hysterical

I have tried leaving him for up to an hour to see if he'll go back to sleep - He never has. He will however, sleep if I lay down with him. He will sleep for up to 1.5 hours if i'm in bed with him. So obviously he is tired, he just won't re settle. The other day I rolled him onto his side (which he normally falls back to sleep, but once I roll him on his back he wakes, or, he'll accidently roll onto his back & wake within a few mins) & patted him bottom for 45MINS! He finally fell back to sleep, but woke 10mins later!

When he gets up, he's so grizzly & whingy, just like he doesn't want to be awake cause he's so tired. It takes about 10 mins for him to 'get over' it

He self settles to sleep, EVERY time. I just put him in his cot & walk out. He may cry for a few minutes, but NEVER needs help to get to sleep. So why can't he re settle himself?

I have tried dropping the morning sleep & putting him to bed a little earlier for his lunch sleep, but he still only sleeps for 20 - 30mins

I have tried to give him a comforter that I have worn to get my scent into it, but that doesn't work either.

I have tried to get him up as soon as he wakes to give him the indication that if he wakes he's up, but he doesn't get it.

After all of this, he refuses to take another afternoon nap, unless his in the car, he will fall asleep.

Please, please, please..... Does anyone have any tips on how I can get him to sleep longer? I'll try anything

ETA : I should mention that he is only 7 months is corrected age. I'm sure babies of this age should be having more sleep than he is