Peanut butter 🥜

So my oil light was on, as I open the lid to replenish it I see this, should I be worried? I put around 1l of 5w-30 in and drove home. Also just noticed I bought the car without an air filter (car was cheap and from a friend), gonna get a new one online but could this have contributed to the pasty oil? Any insights would be nice 😊