courtesy Ariana Grande/Instagram

Ariana Grande has to take care of herself! The songstress has cancelled what was to be her first concert following her breakup with Pete Davidson in October, due to illness.

Grande is reportedly suffering from bronchitis, preventing her from singing, obvi. But fans are speculating there could be another cause for cancellation ...

Ariana's had what she's dubbed "the worst year" -- with the accidental overdose of her ex-boyfriend Mac Miller and her breakup with fiance Pete Davidson right after. Perhaps she needs a little more time to heal before she jumps in front of a Las Vegas crowd to belt out her hit single "Thank U, Next?"

Ariana was set to do a gig at The Chelsea in The Cosmopolitan hotel in Las Vegas on Saturday.