Genetic testing question

Hi today i make 11 weeks & i was offered a test to take to see if my baby has downs but also will determine the gender ! Did anybody else take the test & was it correct in stating the gender for u ! Im on the moon im so excited & so is my family when i found out i was pregnant i had to literally stop them for buying stuff cause i didnt know the sex ! When i get this test done there will be no stopping them & i need to know if its right first lol.