"is it going to hurt my car if I drive it for a couple months until I save up the $800"

Although it takes ALOT of oil covering the exhaust pipes, convertor to ignite it can and does happen. Ever see burn't cars along the freeway and wonder why they burned? It's almost always because they had serious oil leakage which eventually caught on fire as oil is flamable and once it starts, you probably won't be able to stop it. It's more common in summer but it does and can occur anytime. I havent personally seen a Volvo burn due to this but it's always possible if you're leaking enough oil.