Is AUTHOR wrong in the post ? POST : Recently I started to date a girl that I believe is perfect in every aspect. I met her 5 years ago, and liked her since, but only got to date her about 3 months ago.
We have mutual friends, that we like to go out in couple dates. This couple study in her college, and I study 438km away from her, being able to see her 3 days a month.
Since the last time we saw each other we've been planning this weekend, since is her birthday.
Well, we planned going out to eat sushi on saturday, then foing her house. In the sunday, the plan was to go some fancy restaurant with her parents (the birthday was on sunday) and then watch some movies together at night.
It happens that i came early to town, in the friday, and surprised her. While we were chatting, she told me that in the saturday, we were changing plans and going to a birthday party of our friend couple. I really didn't like that she only told me that one day before.
But okay, we ate sushi and passed by the party. Before entering the party, I received a message from the Friend saying that he and her gf were going to my gf house on sunday, night to see movies. I looked at her and asked "seriously?" since she didn't told me. But okay, I got mad, barely talked to anyone in the 20 minutes we stayed in the party, not because the plan changing, but because I got really sad that she wasn't telling me her plans.
But okay, sunday came, we lunched in a incredible restaurant, then we get to go to a water fall, and i gave her the birthday presents. One of them, a neckless with earrings. She liked, told that she  liked very much. The when the couple came, they gave her a necklace pretty much the same. She picked the present and at the same time putted in her neck. 
The dinner started and felt really, really bad. My pressure felt in the ground, and i couldn't chat with anyone. Everyone detected something wrong. My mother-in-law got worried. (Btw my pressure felt not just for that, last night we were togheter until 4am, and i waked up at 6am to go with her family to church, didn't slept since).
She was drinking wine, and asked me to accompany her to her room, where a little drunk she asked what was going on, and i told her "nice necklesses". She got really really sad, but i was sad too. I fell in my knees and asked forgiveness for her for being jealous, we didn't argued or anything. But i felt really really bad, and her too. We got back to the dinner, but everything was not okay. 
Before going to sleep, we texted each other, i apologized more than i should, and less than necessary.
She said that she loved my, sent many audios telling this.
And this morning, everything is not okay. She is clearly mad. I bought some flowers, came to her college, apologized again in the break time. Now I'm waiting her class to finish so i can chat with her properly, but I really think I blew up the relationship with the person that i think about since 5 years ago. Please, while saying YTA, please help me to make this get better.