You should be expecting a score of around 530-550 if this is your score in the major series. Though if your preparation in these 10 days is good enough, you might cross 550. Also, for getting into any government medical college, you should have a score of 550+ in NEET. Also, the competition for those seats in government colleges is very very high, so yes 550+ is the minimum requirement. But depending upon your category it may be variable.