Difficulty swallowing!

I dont know if i'm posting in the correct section but here goes. I'm 29 year-old male (nearly 30) and for the last month of so i've had a slight discomort on the left side of my stomach area. I never really thought much about it until recently where i've been having some strange symptoms aswell. Basically, when I eat in the morning or if I go without food for a long peroid of time, then try to eat I have real difficultly swallowing. It feels like the food gets stuck or it takes my stomach longer to accept the food. This gives me alot of discomfort especially in the morning. It gives me a intense heartburn type feeling (not nice). But, the funny thing is, if I stand up and eat I don't get this feeling as much. Obviously, i've been 'online' to try and find out whats causes this and I stumbled across 'stomach cancer' (paranoia sets in). I do realise that stomach cancer is rare for people my age but i've been a keen bodybuilder for a number of years (10 years) and have always had a high intake of calories (mostly quality foods, not junk food), lots of protein rich foods and lots of powered supplements. Obviously, now i'm beginning to think that this sort of diet might be effecting me now. Can anybody shed some light on what this might be? Or, am I worrying needlessly? Thanks!