2005 Chrysler Town and country blown head gasket?

while driving up a steep incline I heard a loud hiss
coming from the engine compartment. And My
windshield fogged up  Pulling over I found I had
overheated drastically. I opened the hood and there
was no steam, the hoses were still pressurized and
there was coolant in the reservoir. I let the engine
cool and went to get the vehicle the few blocks
back to my home she started right up however at
this point I noticed the power steering was out. I
checked the fuses and they're a good. What
caused this and how do I repair it?