im 17M i keep having these anxiety/panic attacks which has never happened before

so i randomly got like this feeling idk if it was an anxiety or panic attack but my heart started racing and i felt dizzy, i went to the er and they asked me about my sleep and diet which i have been sleeping late and my diet is kinda bad i eat very less sometimes or alot of junk, they said that im fine they did a heart check thingy where they got a chart of my heartbeat idk and that was fine, they said that its digestive problems and i likely have an infection somewhere related to digestion or something, its been a day and idk if its just that im scared and anxious but this feeling in my chest just doesnt go away every 2 minutes i get the feeling u get when ur heart drops and i get scared and the same happens when im trying to sleep the second im almost asleep i get the same feeling and im wide awake