Can a baby show symptoms of teething @ 4 month and the teeth come out @ 11 months?

My son was about 4 month old when he started to show the symptoms of teething (drooling, biting, crying while suking his fist or whatever came to his mouth with anger.) I gave him oragel or tylenol that either of them "somtimes" worked. The tooth came out @ 11 month. my own tooth also has come @ the same age as my mom says. My 4 month old baby girl now is showing the same symptoms. Are they really the teething symptoms. If yes why are they so early comparative to the acctual teething? What can I do to help her relax?