Questions about possible afib

I'm an 18 year old female, recently been having these episodes where my heart will feel like it flutters for a best or two (almost like skipping?) And then it races afterward for a few minutes – but this is probably because I immediately jump up because it scares the heck out of me. The past two days these flutters have gotten more intense, I just had one where it felt like at least 3 seconds long and I got very slightly light headed. Is this afib or just anxiety? I am on no medications – but I am a very anxious person, and this has just made it worse.