3 year old & preschool

I need advice. I recently got a job at a preschool, which works out perfectly for me because it means I can get free child care for my son and eventually go back to school. Im going to be working 5 days a week for 7.5 hour days. However, Im not sure how I feel about my son being in school that often during the week, being so young. I feel bad because its almost like hes jumping right into full school days at 3 years old. I may be overthinking it, so Im looking for some outside perspective. Its been a hard adjustment for both of us. Hes been crying and so have I, lol. So my emotions may just be getting the best of me right now.

So I guess my question would be, do you thunk 5 full days of school is too much for a 3 year old? Should I cut it down to 3 or 4? The only downfall is, I would be getting paid less weekly and may not be able to afford the bills I have. I thought about getting a 2nd job for the other 2 days of the week.