Can cats cause a skunky smell in the house?

I can't tell if I'm imagining the smell or if it's actually there. It smells similar to their butt area after they've used the litter. I started smelling that skunky smell in my room a bit where my cat sleeps with me. Should I just wash the sheets and give him a shower to take care of this smell?

It also could be the cigarettes that I smoke. I smoke outside, but I haven't showered in a few days now so I'm wondering if the cigarette smell is creating the skunky smell instead