Out of control toddler

I desperately need advice on how to get my almost 3yr old under control. Im separated from his dad and every time he comes back to me hes out of control and hates any kind of authority. Since ive had him back hes been the worst ive ever seen. Its a minimum 30min battle to get him to bed every night. I can't lock him in his room as my unit only has sliding doors. Hes been pushing against any type of discipline i attempt. Today was by far the worst he was uncontrollable at daycare which hes never acted like that there. Im suprised his carer didn't ring me to come get him after everything she told me he did today. I felt bloody awful for her and was nearly in tears as she was telling me everything he had done. Im at a loss for words on what to do next