Since you are still new to the game, it is okay for you to just focus on the basics of healing. Anticipate the damage spikes on the tank and party and mentally prepare what heals you are going to use next.

However, once you get more experienced with healing, you may see periods of time where you can safely supplement dps for your group. A great healer is able to identify these potential dps opportunities without putting the party at risk. Also, while a Scholar has certain dps advantages in raid environments, a White Mage can also output a significant amount of dps so that should not be overlooked.

Most importantly you should just have fun playing the game. Some people are just really jaded and have attitude problems. Just have fun and relax and do not let negative people put you in a bad place.