Please help me I’m getting so frustrated my partner works nights shifts and I also have a 3 year old

My baby is 8 weeks old he sleeps great once he’s actually asleep generally asleep between 8 - 9pm and waking for a feed between 1.30-2.30 then sleeping until 5.30-6.30 when it’s bed time I bring him up put his little mobile on swaddle him (if I don’t swaddle he wakes him self up every hour with his arms) and then put him down and sit on the bed next to him so he can’t see me unless he starts crying I of course reassure him he falls asleep 3 or 4 times but wakes himself back up and every night takes up to an hour and a half until he’s findally in a deep sleep I get so stressed out I just start crying I’ve recently quit smoking and all I want to do is smoke every evening feel like giving up what am I doing wrong 😭