When you have a new girlfriend, no matter what her age, buying presents for her is easy...or it should be if you realize that a gift is just a communication. You're just getting to know her. What on earth do you have to say that isn't better expressed in words?
In the very early stages of a relationship...when you've only had two or three dates...in most cases you shouldn't consider buying your new lady friend a gift.
But there might be a couple of exceptions to that rule and worthwhile putting into practice if you think you can pull it off in a deliberately light-hearted manner.
If an event like Valentine's Day or her birthday just happen to correspond close to a date night...go ahead and acknowledge the fact...but don't make a deal of it. Don't purposely make a date that falls on the event, but if it happens accidently don't sweat it.
At some point during the evening you can say your version of . . .
"Hey it's Valentine's Day (or some other celebratory event) tomorrow...let's go over to Starbuck's and I'll buy you an Iced Peppermint White Chocolate Mocha for the hell of it...or should we go track down a chocolate sundae?"
You're in charge. Don't spend more than $5.00. It is just an innocuous acknowledgement of the occasion. That let's her know you aren't stupid enough to not realize that there are people in the world who make a big deal about giving gifts.
Better yet, it also lets her know that you aren't stupid enough to pretend that those occasions are meaningful at this stage of your relationship.
Depending on how things develop between you and the lady you might want to keep the gift giving at this level for awhile longer...months if need be.
But if the relationship feels like it's going somewhere ... what presents for her should you consider then?