2007 Toyota Camry Engine problems

I had my 07 Toyota serviced at the dealership and they didn't replace the engine oil. The vehicle was driven around the garage and parked outside and left running while I paid the cashier. Once I started to leave I noticed that the on board computer indicated that there was no oil pressure. I pulled up to the service center and check it out. The car's dip stick was dry as a bone. After having them add 5 qts of oil the car seems to be running ok.

Question- Am I in for some expensive repairs in the future?
What should I do or look out for?

Thanks,
M. Goff