Heart flutters or thumps once or twice daily. cardiologist says it's normal. this is new, seems more after having a beer. can it be afib?

AFIB: Afib is unlikely in a 26 yo unless they either have a congenital heart conduction issue OR they are doing drugs like Cocaine or meth. Its more likely you are having ectopic (extra) sinus beats, sinus ventricular tachycardia and/or occasional premature ventricular beats. Stress, anxiety can cause the above. You could see a cardiologist and wear a halter monitor for 24 hours.