ok heres my advice

ask her whats wrong
if she tells you "nothing" then tell her youre going to act like nothings wrong and you dont want any drama

if she tells you "you should know" or something along those lines
ive had my gf do that to me and i tell her:
i cant read your mind. if somethings bothering you you need to tell me so i dont do it again. same as youd want me to tell you something you do bothers me