Am I entitled to child support?

I have a 19 month old son whom the father and I agreed to share physical custody but I retain full legal custody of. Our son spends 3 nights of the week with his father and four nights at his home with myself. This agreement was made after I filed for child support when my son was 6 months old and his father was not active in his life. I discontinued filing for support after the father of my son and I agreed to the above split physical custody and that we both pay equally towards expenses for our son.

My son has been in daycare for which the father and myself have shared equal cost for. Recently my son was kicked out of daycare due to father's nonpayment. I have documentation of 10 different times when checks have bounced or payments have not been made on time to our son's daycare. These recent events have made it troublesome for my son to attend daycare because week to week I do not know if his father will being paying his half of daycare although he is using the facility as much as myself throughout the week. Am I entitled to some form of child support to guarantee that he at the very least continues to pay for daycare.