Hi Iamprithwish
Your mock scores say your content knowledge is good. Any drop-off in score on the actual test would be more likely process related.
In the last two weeks focus heavily on improving your in-test strategies across quant and verbal.
People fall short during the actual GMAT test due to failure points like these:
1. Missing information that's given or is there for the taking (by minimal preprocessing) in quant questions
2. Failure to visualize word problems (so you miss opportunities to break thru on harder problems)
3. Wasting opportunities to eliminate answer choices in SC
4. Not closely restating the core argument in 10 words or less in CR
5. Making what seem like silly calculation errors which are actually due skipping calc steps (acting like a quant wizard)
The GMAT rewards you for core knowledge of math and English but equally for great processes. When you fully understand the test (which most test takers don't) and you adapt your processes to it, you'll hit your full potential on your test day performance.
I help people with this exact scenario (last minute retake coaching) and I'd be happy to talk with you on a call. We can also schedule a FREE diagnostic session to unearth your key gaps going into your test and identify the quickest path to fixing them.
Let me know if you're interested.