Our setup is this - we have a drilled well and a dug well, both come into the house and have their own breaker switches, and both come through the same pressure tank in the basement. The dug well has a typical indoor water pump and the drilled well has a sunken pump.
At first we were puzzled because it seemed totally random, but as time goes by we've concluded that we lose our water pressure whenever there is a long, slow drain on the water - as in, if the toilet runs for several hours, when the water softener system runs through its flushing cycle, or when the dishwasher runs. By contrast, we can have a typical morning with two showers, washing dishes in the sink, and doing 2-3 loads of laundry, and have no problems whatsoever.
Have you heard of this kind of thing happening?
I guess having one tank with two pressure switches is possible. If that's what you mean.
Obviously neither of these wells can keep up with demand, so you run out of water or pressure or both. If this is the case, you might want to look into a cistern system to give yourself more stored water for future use.