Juice it up, take a vape.
If something has gone bad (coil or wick) you'll know very soon. Just don't fire it up un-juiced.
Worst case, rinse it out, take out the cotton, check the coil (dry burn/pulse), re-wick and start all over.
It's not different to an RDA left on the vape desk. Make sure it's squonking properly too...