how long will i stay at 2 cm before i get to 3 or 4
You are now at 2 cm which means you're in early labour (2-4 cm).
Contractions start farther apart, 10 to 20 minutes apart and are short only lasting 30 to 60 seconds long.
Early labour can last up till 2-20 hours!
Good-luck and Congratulations!