Ok buddy, you may follow the advice from 'Justme'and in so doing you will be operating by guesswork and mindreading.If you do believe that your girlfriend is attempting to make you pay more attention to her by trying to make you jealous, then by showering her with attention you are reinforcing her behaviour.That means that you can expect a lot more of this kind of stuff.Why? Because she saw that it worked on you! Is it OK with you for her to do this ? Obviously not, otherwise you would not have been distressed by it and then post it on this site for advice.
Her reasons for doing this are really known only to herself.The point is this -her attempts to make you jealous are crass and infantile and are devoid of any respect for your feelings.Why would you want a girlfriend who does that to you?