constrained
kənˈstreɪnd
adjective
appearing forced or overly controlled.
he was acting in a constrained manner
unnatural,awkward,self-conscious,mannered,artificial,wooden,stilted,strained,forced,contrived,laboured,inhibited,repressed,uneasy,embarrassed,tongue-tied,restrained,reserved,reticent,guarded,distant,aloof,cold,cool,stand-offish