Hi,
After going through your case I would like to advise you that report everything happened with you to your teacher, and get medical examination done.
I want to know-
1) Whether you really want to go to trip.
2) Any kind of mental tension is there.
3) Any heart problem in your family.
In your case there are following possibilities-
1) Occasional rapid heart beats in a healthy adult in the absence of giddiness, sudden black outs is most of the time normal.
2) Anxiety / panic episode though its possibility is less as it is your first episode.
3)
Cardiac arrhythmia (abnormal electrical activity of heart)
If it happened repeatedly then it is better to
consult cardiologist and get the following tests done -
1) ECG done during period of fast
heart rate it can give more information.
2) Holter's monitoring or electrophysiological test for heart.
3) 2DEcho (
echocardiography of heart)
4) Serum electrolytes, renal function test.
5)
Thyroid function test.