Singapore Immigration review: immigration officer

I just arrived in singapore and i just received a bad welcome from the singapore immigration officer.First of all, i admit my mistake yeah it was my mistake that i did not see 2 collumn that must be filled in in the immigration form and i did not fill that 2 collumn.However that is not acceptable for immigration officer with class like Singapore insulting tourist from another country.He insult that we did not have eye and we did not qualify to understand english. Well its a common mistake as a human sometimes we make errors and he insult 2 old people which is my parents.I often visit singapore but this is just ruin my first day in Singapore. I just hope in the future they can change their attitude, become more friendly and patient to all the tourist.I know not all the officer have attitude like that.