Consider getting the ESR of the 670 to see what to potentially work on. If you share it here (after wiping any personal info), people may also provide some specific suggestions.
Ultimately, because of "...my college in 12 days. I won't have time to prepare in my college." you'd probably want to retake perhaps 10 days from now (if you want to take it beforehand). Not saying it's an ideal timeline per se but fair to say some people have improved their scores on quick retakes. Had a retake student who ended up going from a 700 to a 760 in about 10 days, for example.
Perhaps take a day or two to think over your options/see how you feel.
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