possible consequences for underage drinking under PA criminal code

Underage Drinking: I was recently at a wedding reception with some friends and drank a few drinks.I am 20 yrs old and attending college. As we left two cops followed us until we arrived at our hotel where we got out and quickly were questioned by the police. Only me and 1 other friend were under 21 and when i was asked if i was drinking he said he could smell it on me. I told him i had around 5 beverages at the reception. My citation says that i admitted to that and was charged with underage drinking. If i plead not guilty is there a chance i could get it changed into a disorderly? Also this is my 1st offense and havent been in trouble before. - Is this your question? Add additional information