Splork, you need a proper medical assessment.
There are a few issues with your post:
a) Yes, the antacid medication may be hiding an underlying serious condition, which could be treated properly.
(The risk of this depends on lots of things, which your doc. should elicit - it would be unusual in some one of tender years - ie under 45ish.)
b) There may be an underlying condition causing your symptoms which could be erradicated quite simply. (there is a germ which is sometimes responsible for heartburn called h-pylori which is simple to test for, and simple to treat.
c) My colleagues may disagree with this, but the dose of ranitidine you are taking could be seen as being sub-therapeutic, ie not enough to do the job properly. (if your symptoms keep returning then I would suggest you need a different dose / rgime of treatment.
Finally, don't forget the lifestyle issues- usual culprits I'm afraid - fags, booze and rock and roll lifestyle !
Final tip - chew your food well, let your teeth do the work, not your digestive tract, and sit down for 20 mins after eating.