I'd definitely agree - go ahead and sit down and take a full mock exam. Are you following a dedicated course of study, or are you just doing questions from the OG/GMATClub? In order to get the most out of your study time, it pays to be systematic. Once you take your mock exam (or a shorter
diagnostic if you don't feel you have the time to do a full test), take a look: where were your strengths and weaknesses? What were the questions you should have gotten right? The questions you could have gotten right? (And the questions you could someday get right.) Plan your studying to really address the first two first, leaning really heavily on your
error log to track not just what you got right and wrong, but why you got them right and wrong.
All that said, what are you doing right now to structure your prep? How long are you spending each day? What are you doing during that time? (Is it mostly just doing questions, or have you set a schedule for yourself with goals?)