Eating disorder?

I used to never have trouble eating when I was younger, if anything I might of ate a lil too much. I was a lil chunky and then when I turned 15 I started losing weight. At first when going to family events or seeing people I haven’t seen in awhile I got a lot of complainants about my weight lost. I had no idea how I was losing the weight, I rarely excised and wasn’t that active. I didn’t notice a change in my eating habits, but it felt good. I kept losing weight and now I’m around 115, I’m 5’9. I work in the restaurant business and I’m constantly on my feet. My eating habits have massively changed recently. I noticed that I barely have eaten anything these past 3 days and just got done working 13 hour days over the weekend. I’m definitely not eating enough for how active I am. I told myself today I will eat no matter if I’m hungry or not. I woke up and felt really weak, I went back to sleep woke up later in the day and felt really nauseous. I decided to drink a protein shake and eat some toast. I felt even worse. I then went to the store to get some soup. I had threw up my shake and toast in the parking lot. When I had gotten home I made me some soup and had some ginger ale. I threw up the soup. Then threw up again a while after. I decided to eat something else later in the night taking small bites at first and then threw up again. A lil after i tried another attempt and the same thing happened. I’m going to try and eat again tomorrow and see if I’m able to hold food down. I’m trying to eat but it’s just so hard. Me not being able to keep food down hasn’t happened until today. If this continues tomorrow should I go to the hospital? What foods should I eat to make me feel better? What should I eat to help me gain weight in a healthy way? I never thought eating or gaining weight would be so hard. It isn’t my intention to lose weight or not eat. I hate throwing up and I do love eating. It’s just recently become a problem.