Pressure in stomach & muscle weakness

[paris316]

Hello...I get a pressure in my upper stomach that goes up to my throat causing my heart to beat fast.It seems it occurs when I lift anything with weight like my 12 lb.puppy.It lasts for a few minutes & is terrifying to me.I was diagnosed years ago with gerd.Not sure if this is related to gerd.I notice though it acts up when I have a gassy stomach but also trouble passing the gas easily.My stomach feels nauseous too.I get mild heartburn but not too bad.It does give me anxiety after the episodes.