2006 Jaguar X-Type Smelling gas fumes/ burning smell throug

My husband changed the oil, since then, when I turn the defroster or air conditioner on, I also smell some kind of gaseous fume. It's so bad that I have to switch off the vent, but even with the vents closed/off I smell that same gaseous smell. After a drive and I park my car, there is a burning smell coming from the hood. Everything appears in tact (no fires underneath the hood), but there definitely is a smell because the garage totally smells like burnt rubber. Any info or advice would be appreciated. Thank you!