What did the oil look like besides being unusually high? Was it muddy or did it have the consistency of a chocolate milkshake? Have you checked the coolant level? If so, was it OK, and what did the coolant look like? Did the vehicle ever overheat?
I think these engines are known for head gasket trouble, and it’s quite possible that this is your problem, but I wouldn’t jump to conclusions. Although it’s quite possible to have a head gasket problem without water/steam coming out of your exhaust. (keep in mind that in cold weather, some steam is normal too) I’d have it towed to a mechanic and checked out.