It's like lifting weights ... lift more, work harder.
The amperage on the pump is based upon the maximum load under normal conditions. If you're not lifting the water that high, it will draw fewer amps.
You'll still need to allow for the full current inruxh when the pump starts, though ... that's likely when the breaker is tripping. I'd see if I could go up a breaker size if the existing breaker is less than 5x the full load amps on the nameplate.
If you can take the pupm out of service, I'd try to spin the thing by hand. It ought to spin freely in BOTH directions- and you ought to be able to feel if a bearing is binding.
