Running Laps In Back Yard. Suffer Chest Pain. Feeling Heart Burn. Feeling Lump In The Chest. Suggest?

Question : Hi,

I'm a 56 year old man.....good health, but I do smoke. I have worked out 5 times a week for years. Earlier this year, I did the Insanity workout program for over 3 months. Then I went back to lifting weights and started running laps in my back yard. Starting about a month ago, I would get a pain in my chest every now and then when I would run. Then it would happen occasionally when I would lift. then it started at night and would wake me up from my sleep. When it starts, it starts feeling like heartburn up near my throat, then moves down to the middle of my chest. It gets tighter and tighter and turns into a dull hard pain. It normally would last about 30seconds to a minute...then suddenly go away with a feeling of having a big lump stuck in my chest that suddenly goes down. Over the last two weeks, it can occur when I exert myself....like if I carry something moderately heavy from my garage to my house.Last night, I woke up around 2 Am and got up to use the bathroom. It's only 30 feet from my bedroom. When I got to the bathroom, then pain started and got pretty hard. It made me site down cuz I felt a little sick. The big difference this time is that my forehead suddenly broke into a sweat...the kind of sweat when I wiped my forehead and it was wet with beads of sweat. It lasted about a minute and a half. When it subsided, it was like that lump down in my throat dropped into my stomach....and I felt fine. This has started to worry me now.