I m 18 years old and lately my heart s been beating really fast. like 104-114bpm when im just seated down working on projects. or sometimse 94bpm when I m standing up or when i walk a little. then later I d have a hard time breathing. Sometimes, a few minutes after I wake up, even though I m still lying down in bed, it starts beating fast like from 90-100 bpm. It s been a week since it all started. Now I m having a hard time going up the stairs when I used to do so easily before and I ve been getting tired easily... Also, when my heart doesn t beat as fast, like let s say, 80-82bpm, it get s really loud instead. Really loud that I can hear my own heartbeat already and sometimes it makes it hard for me to fall asleep. Then one time I started shaking for no reason. It started from my neck then it went to my tummy and It went from there spreading throughout my body. My head would shake the most.Should I worry about this? [my mom texted our doctor and said that I might just be tense or stressed or not getting any sleep] my mom doesn t think I should get a check up...