Hi tushartiwari4u,
First off, a 650/Q48 is a strong score (it's right around the 80th percentile overall), so it could be enough to get you into your first-choice School. As such, a retest might not be necessary. Depending on the Schools that you plan to apply to, you would likely find it beneficial to speak with an Admissions Expert about your overall profile. There's a Forum full of them here:
https://gmatclub.com/forum/ask-admission ... tants-124/The process of applying to (and ultimately attending) Business School will require a big investment of time, money and energy on your part, so you really should make sure that the Programs that you apply to match your career goals/needs. There are a variety of factors that go into selecting the Schools that you'll apply to. Instead of just applying to Programs in which you might have a good chance to 'get in', here are some other things to think about:
1) Is there a particular company that you want to work for or industry that you want to work in? Certain degrees are more appropriate than others if you have a specific career goal.
2) What do you want your MBA to do for you?
3) Do you want to go to School full-time or part-time?
4) Are you willing to relocate? Are you comfortable with working through a program that is primarily online?
5) Are you going to be applying for scholarships?
Etc.
It's okay if you don't have answers to any of these questions just yet, but you really should try to define all of the important variables in terms of your goals, so that you can tailor your entire approach to getting into the best School that matches what you're looking for. By extension, once you have a list of Schools, you'll have a better sense of whether you should retake the GMAT or not.
GMAT assassins aren't born, they're made,
Rich