So fast

I have here in front of me an application to the preschool that my youngest son, M will attend this fall.  I have enjoyed these past 3 1/2 years with him so much and I can't believe he's going to preschool! M has actually been asking to go to school and he wants to go to school a lot he's told me.  We are going to enroll him for 3 1/2 days a week.  I know in my heart he's  ready but am I?  M is at the stage now where he get bored easily and finds trouble when he's bored.  He loves his time with me but I can't always entertain him every second.  He needs school.  He's very smart and knows all his letters, some of his numbers, he can count and his vocabulary is great.  I'm going to miss my boy.  But this time will be good for us and I'll still have 2 other mornings a week just him and I for one more year.  My hubby pointed out that March, April, and May are the last full months of just him and I every day during the week.  *sad face*  I am going seize these 3 months and fully enjoy every moment with my baby.