I'm so sorry this has happened to your son and you. While my daughter's mental health difficulties have mostly not involved psychosis, I understand the fear and despair that a parent feels when a beloved child has an acute mental health episode.
Your son is in the right place to get help. Don't feel guilty - you could not have seen this coming, and nothing in a parent's experience equips us to manage a psychotic episode.
With ongoing support from you and mental health professionals, this may never happen again (and 48 hours without sleep would send anyone into a bad spiral). Encourage him to accept help and advice, stay close to him, let him know you are his biggest fan. If he is willing, go with him on the journey of learning what he can do to look after his mental health. You can help him - healthy eating and keeping mentally and physical active really do make a big difference to mental health.
Be prepared to experiment - if medication is prescribed, it may take some time to get the type and dose right for him, and he needs to be honest with the professionals about what works and doesn't work.
Be prepared for setbacks but do stay hopeful - because that will help both you and him.
Wishing you all the best.