It  happened agaqin just the other day at school  please help understand what is going on with my heart

OK so my hear was racing at 117 beats per minute the other day at school ( a little lower than last time )  and I didn't do anything that would provoke my heart to beat that fast     no running    no nervious feelings   and I wasn't stressing out about anything  so it can't a panic attack   could it    I wonder?     So   please help me understand what is going on with heart     it would really help me out    I have a friend on here to zdesotelle   and he's posting questions as well    about me and my heart problems    so please get back to me as so as possible!


Thanks!!!
Love
tally_la