What Treatment Should I Follow After Having Heart Palpitations?

I'm 18 years old, and took diet pills (Zantrex-3) yesterday. More than 8 hours later, they finally hit me. I felt nauseous, had headache, threw up several times, had tremors, and then even began having panic attacks. I went to the emergency room , and this all still continued even after sitting in the ER for two hours waiting to be seen by the doctor. He gave me a sedative to slow my heart. In about 20 minutes (2:45AM), it finally kicked in. Waking up this morning, I feel drained and my head is throbbing, with my heart still kind of racing. Is there anything I can take to lessen my heart rate, or can I call the ER and request a prescription (or will I have to be readmitted to get one)? What foods should I avoid while waiting for the pills to finish passing through my system?
My pulse is 110.

What is your heart rate now. If its 100 or less you are fine and if its a little over 100 I wouldn't worry too much just check frequently. However, if its above 120 go back to the ER.