That depends on how long the immigration inspector authorized you to stay when you entered the U.S. If you were authorized only 6 months and stayed longer than that without obtaining an approved extension of stay from the U.S. Bureau of Citizenship and Immigration Services, you are ineligible to re-enter the U.S. on your B1/B2 visa. Please do not try to travel to the U.S. with your visa – you will be intercepted at the airport and returned to Poland at your expense. Per U.S. immigration law, because you overstayed by more than one year, you are ineligible to obtain a new visa for a period of 10 years.