Hello
Having your experience myself and not being a native speaker, I studied for 7 months, appeared for the exam and got a 620 with a V32.
Thinking that I can improve to 700 and that the problem was with my verbal, I studied for another six months, sat for the exam the second time and, of course, a drop 7 points, such a shock.
By then I realized that there was something wrong with my conceptual understanding of verbal. I came back and started from the scratch again. This time with a focus on understanding the concepts first and then solving related problems.
Now, my suggestion is how much time do you have and how willing are you to reach your score? If you have time and willingness, I suggest you go back, start from the scratch, learn the concepts, start doing a lot of practice on those concepts and build on them.
In terms of Verbal, if you have less than two months, first work on your strengths SC and CR up to 40 level since those areas would help you a lot. The way it does is that it will land you on higher level RC questions and therefore, your chance of scoring higher on verbal will increase. If you have more time, 3 to 4 or even more, then start on all, perfect your SC and CR and improve your RC. First, learn to comprehend the passage reading then focus on questions types since there are only a handful of questions types on RC.
One thing that I cannot emphasize enough is that you need to practice only from official materials and supplement your learning, practice, and studies with Videos that only teach you official materials. There are a lot of those videos, especially on Verbal, taught by Ron from
Manhattan GMAT.
The same problem that happened to you happened for me on Quant section. I stupidly spent 6 minutes on the first question digging a well for myself that I couldn't get out of it at all.
I believe getting a higher score is doable as long as you believe in yourself that you can get it.
Best of luck and wishes for everything.