From 510 to 650 on the GMATPrep, real test next friday

Hello experts. Three months ago I started studying for the GMAT. Before that I did not even know what the GMAT was. Before anything, I took the first GMATPrep because I was confident enough that it was going to be easy as I graduated first in my university ranking. However, it has been three years since I finished my bachelor's degree and my current job is not the best activity to keep the even the basic math concepts in my head. Obviously the result was awful, especially the Quantitative: Q28, V33, Total 510. But when I looked at the answers of the Q I realized it was not rocket science, but basic math concepts which I had forgotten. Moreover, as I was not well-trained to consider timing, I guessed the last 6 questions in the Q section. On the other hand, I ended the Verbal section 10 minutes earlier. I am not an English native speaker.

Then I started studying without any material, reading things in the Internet (that's how I got here). But I realized I needed good materials and a study plan so two months ago I got last OG the MGMAT books. I worked with all the MGMAT books (except RC) including the exercises there provided and did around 1/3 of the OG Quantitative problems and 1/5 of the Verbal problems. I worked harder on the Q section because I felt very confident with the V.

Yesterday I finished the MGMAT guides. My last one was the Geometry one. Today I took the second GMATPrep. The result was Q44 V36 Total 650. I could not believe two things: how much I improved on the Q and how little I improved on the V. I want to score 650-680 on the real test next Friday so any advice for these last 4 days would be appreciated.

I reviewed my Q mistakes and many of them were silly mistakes, for example not paying attention when is says "three even numbers..." responding it is not sufficient when it is, and things like that. On the Q section my timing was perfect. I was never in a rush and got to the last question with 2:30 minutes left.

On the V section, I had to solve the last 10 questions in maybe something like 14 minutes, so I did those questions very fast and got many mistakes there (see images attached). But after working so hard with the MGMAT guides and feeling confident about it I expected a better improvement than going from 33 to just 36 after three months of study. I tried to see where I had the most mistakes and the conclusion is evident. Out of 13 RC I only got 1 wrong, out of 11 CR I got 3 wrong, but out of 17 SC I got 8 wrong. Obviously my big problem seems to be SC.

I have a full time job so I will only have the afternoons from Monday to Thursday for practising. I will try to re-read the SC guide and make more OG SC exercises. Maybe on Thursday I will review some Math fundamentals just in case. Despite the results of this last GMATPrep test, the Q section stills makes me more nervous than the V section. I do not know why.

Any other advice?