Do I need to file for a waiver?

In regards to unlawful presence as it applies to the 3-year and 10-year bars under INA 212(a)(9)(B)(I) & (II), you do not need to file a waiver for unlawful presence as long as you departed the United States within 6 months after your 18th birthday.

How many days after your 18th birthday did you leave the US because you start accruing unlawful presence time when you turn 18 and if you were still in the US for 180 days after your 18th birthday (which it looks like you were) then you are barred from reentering for 3 years (but it's already been that long). So, assuming they count it correctly and it has now been 3 years since you departed, you should be eligible for a visa. Please let me know if you have any additional questions or how I can be of further assistance to you in this matter.

If you were under 18 years old when you left the U.S. on Feb 28, 2010, the period of your presence in U.S. prior to your to your departure should not be considered unlawful and so, you may not need a waiver. Even if you were over 18 years at the time of your departure, the inquiry regarding unlawful presence is not at an end and so, you must next calculate how many days you were in the U.S. after your 18th birthday. If you did not spend more than 180 days (after your 18th birthday) before leaving the U.S., the unlawful presence bar may still not apply. From my experience the sticking point in cases such as yours is to convince the consular officer that you left the U.S. on a particular date if you take the position that the bar does not apply to you. Also, please note that there may be other factors that are relevant to the issue of your eligibility to return to the U.S. and so, I suggest that you consult with an attorney who must have all the information regarding your case and carefully assess your case in a more detailed manner.