I think what you're hearing is the bearing and cup play in one or both pedal axles. Do you
hear/feel a click when you hammer hard, but it's not there when you're just spinning easy?
Do you hear/feel a click at the same point in each crank revolution? If you pedal with just
one foot (surprisingly difficult, at least for me) does the noise go away depending on which
foot you lift off?
Can you reproduce the noise while the bike is stopped, by grabbing one pedal or the other
with your hand and pulling/pushing hard up & down?
My own half-vast (say that fast) experience is that BBs squeak or chirp. A clicking sound
almost always comes from the pedals, chain, or rear derailler pulleys.
Before you do anything to the BB, buy another set of pedals... and spin them on. Take a ride.
Platform pedals wear out pretty fast, especially if you're a hammerer like I am. Performance
sells a set for $21.99 (00-0147) that I get between 10K & 20K miles out of. Or, basic platforms
can be found at some of the online retailers for as little as $10.