Concerned about my health, need advice

My symptoms started in early December. My heart would suddenly race and I'd become very light headed and confused. in January it twice as I laid in my bed asleep. one morning I woke up, very dizzy, had a pain down in my right arm, I didn't know where I was for a few seconds, my heart was racing. I thought I was having a stroke. this was around the time I started having pain and pressure up in my right upper quadrant beneath my ribs. so far I've never had jaundice or anything. the pain was coupled with diarrhea that would not seem to go away for days and long bouts of brain fog. the brain fog comes and goes and stays away for longer than it did earlier in the year. the pain has settled in the lower right part of my abdomen. I sometimes get it underneath my right shoulder though. food does not seem to be digesting properly. I occasionally have pale stool. My stool is normal a lot of the time but right now its runny and black, possibly from pepto bismol, and has been for about 2 days. i still get hungry and i still eat.