I Have Add A Subtle Change In My GI Tract

I have add a subtle change in my GI tract that has been constant for about a week. I normally am very regular and don't have trouble with anything I eat. My diet is fairly constant and healthy. I feel full all the time, although my appetite isn't affected. The fullness makes me not want to eat but because I take metformin I have not stopped eating just a little less. When I do eat I don't feel worse or nauseous but constantly full. My bowel movements are now once a day when before it was 2-3 x day. I have a very slight heartburn feeling which I don't ever have normally. What ever I do (excercise, eat, sit) it doesn't get better or worse but it's not a normal feeling
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