Britt.....I have no idea what causes this but I can tell you I have the same exact symptoms. I have the skipped beats and I too can feel my heart beating really fast but not hard beats feels kinda like my heart is shaking in my chest. I have worn a heart monitor and all they told me was they saw skipped beats they didn't tell me if it was pac or pvc or what it was just that I wouldn't die from them. I have anxiety also but seems like my heart acts up when I am at rest too...just watching t.v or on the computer. I have triggers though like bending over or twisting or laying on my left side trigger it to skip beats or start beating fast. It scares me to death, I am sorry you are going through this too. You will have to let me know what the cardiologist tells you. I would go back to mine but I have no insurance so I just try to accept that its something I have to live with and its not going to kill me. Hope you get some answers to what is going on.