I smell strange odors at night. iin?

Most people don't know this, but there is such a thing as olfactory (scent-based) hallucinations. You should look into it.

Try some saline nasal spray. See what happens.

Vaginal yeast is growing in your nose. Once you get it on your sinuses, it'll stay there for years in a dormant state.

OP Your old panty stash absorbed water from a leak in your basement and was revived. You need to do some repairs.

Perhaps a shower would help? And to wash the linens once a year or so?

You are smelling extra-terrestrial aliens. Nothing to worry about. They give you harmless body probes while you sleep to amuse themselves.

Attention everyone: In the natural world, vaginas do not smell like anything. If your girlfriend's vagina has any sort of oder, report her to the authorities at once.