Graduate/Direct Plus Loan

So I applied for the Grad/Direct Plus Loan for the summer, for $4300 and I got approved for it. My school received my paperwork and says it will process in early May. I got an email from my school counselor or financial aid representative saying she received it and processing early May. I maxed out my yearly $20,500 or whatever it is. Anybody know how it works? This my first time applying for this.