OT for sensory integration for 3.5 year old

Hey moms!

I’ve been feeling overwhelmed with my 3.5 year old son. He has yet to be potty trained still, that’s been a harder struggle than I expected. And he was observed at his preschool 6-7 times by someone & she said he could def use occupational therapy for sensory integration. So we started going once a week, he’s only been twice so far. And I just feel like I’m putting this pressure on myself to “fix things” fast to help him at preschool which is causing me to feel overwhelmed. I was curious if anyone else had done OT for sensory integration? And how much it helped? And any words of wisdom to get myself to calm down, ha

Thank you! :)