My flight arrives at PVG at 5:10am and I am supposed to go to SHA for my second flight.

Don’t worry. Upon arrival at the PVG, you can take the airport shuttle bus line 1 or the subway line 2 to Hongqiao airport directly. The shuttle bus’s duration is about 1 hour, and the subway ride may take 70 mins. Both of them are doable options.

Both in the airport and the subway, there are English signs and broadcasting, so you will find your direction easily. Besides, your time is sufficient, and you will not miss your second flight. Don’t worry.