32 weeks 5 days, had to be given Terbutaline to stop contractions!( Long)

So I woke up around 11 with a stomach ache and nausea. I ended up having diarrhea all night and constant nausea (no vomiting). I was convinced I had food poisoning. The cramps were awful and I kept getting chills and sweats. Well around 2am I started getting what I thought were Braxton Hicks, I've been having them daily since 15 weeks! I was sick all night. I finally fell asleep around 8am and slept until 11am. When I woke up I knew I had a fever 101.3. And awful lower back pain. I took Tylenol and a shower to ease the back pain. Still having BH. I started thinking back to my first labor and I had all back labor, so I had hubby take me to the hospital. They put me in l&d right away on the monitor. I was contracting every 1-3 minutes. They swabbed my cervix to check if I was in pre term labor. They said I was contracting bc of dehydration. Well after two bags of fluid my contractions were getting stronger and closer. And my temp was back up. The Dr came in and said well your not in labor your swab came back negative!???? I was so confused. How was i not in labor but contracting stronger and regular? But I said okay. Well after three bags of fluid, my contractions were still coming and getting more painful. They decided to give me the shot. Which btw makes your heart pound out of your chest!!! Thank god this worked. The next hr I only had about three small contractions. My concern is if I wasn't in labor what was going to happen if I didn't get the shot!??? And what happens if they return!? Has anyone has a similar situation, if so how long did you last before you went into actual labor!????