11 month old refusibg to sleep

Please help, i am at my witts end.
My DS is almost 11 months old. Previously when put in his cot he has settled himself off to sleep 80% of the time, the other times i just have to pat/shush him and he goes off to sleep. But recently when put in his cot he screams, when i go back in he thinks its a joke, he laughs and kicks his legs etc. I cant pat/shush him as he struggles out of my touch whenever i put my hand on him, so i leave the room and once again he screams. This goes on for hours. I know he is tired as he has just cut down to one day nap, maybe he is overtired? Last night it took 3.5 hours to get him to sleep, today for his day sleep its taken 2 and i have ended up getting him up. I am usually so upset and sobbing by tjis stage, i really dont know what else to try. If you have any advice please share as im desperate.

Ps i have tried leaving him to cry but find it really difficult and he doesnt seem to calm down.

Edited by hayley1

Hi I was wondering how you were getting on as I am having a similar problem with my 9month DD and am also about to lose the plot!
We had the MIL come to stay for a month in March and she got a little unsettled then and wasn't doing great with her last day nap and was waking at about 5am, I would feed her and she would go back to sleep until 8am so not much drama. Towards the end of the stay she would start waking earlier in the night and then earlier in the morning. Two weeks ago she got a virus and was quite ill so she was held and was BF every couple of hours to keep fluids up (as told by hospital). Now she is waking practically every hour at night, not feeding properly and not eating as much as she used too. I am pretty sure she isn't teething but we are giving her pamol each night to get her settled. If I go in and pick her up she gets all wriggly so I can't even cuddle her back to sleep. If I leave she just screams and she also screams if DH goes in ... I haven't slept for 3 nights now and need help please!

Thanks :) We are back on track for most sleeps. During the night if she wakes I tend to feed her cause I think she is hungry/thirsty. She is doing better during the day. We also put a chair in her room and sit there not making eye contact with her. I think she just got really unsettled from being sick, she is a baby that is easily overwhelmed so it kind of made sense. Glad things are back on track for you too