Yes, 2 - 3 months is plenty of time to get your score up. The questions you'll need to master are the more complex versions of what you're already answering.

Once you also gain full fluency of Data Sufficiency, you're good to go, as well. I suspect you'll pick up a bunch of points, just by understanding how the answers measure up -- for example, if (1) works, the only choices are (A) or (D),etc. There are tricks and short cuts, all described in the various test prep books.

If you want to streamline your efforts a course or private tutoring will get you there. If you want to work on your own, there are books and online support stops, like BTG. The bottom line is that some types of questions you need to do efficiently and correctly so you 'borrow' time for other questions which will take more time.

Your score is a good (not great) starting place. Remember the test score is usable to apply to business schools for 5 years.