You don't need a booster, there may be something wrong with your pressure tank. Every well system has a booster (pressure) tank that acts as a storage tank and booster system.
One thing may be happening, you may have a pressure tank that has lost its air on the inside. All pressure tanks use air (either behind a bladder or in freespace) to compress and provide the pressure at the volume you need. At your tank, first check to see if the pressure in the tank is at least 45 psi. On top of the pressure tank should be a small valve that looks like the valve on a tire. Use a pressure gauge and check and see what it registars. If its less than 45 psi, use a tire pump and increase it. If you have the old style without a bladder, buy a new bladder tank. I use 30 gallon storage bladder tanks. This gives you a full shower, before the pump kicks on.
If there is nothing wrong with the bladder tank, your pump may be set too low. I would get a well man to adjust it for you. You can really mess things up if you do not know what your doing. The basic premis though, is there is a high limit switch and a low limit switch. The high one shuts the water off at its maximum setting, usually about 45 psi, though I set them to 55. The low limit turns on the pump when the setting gets 20 psi below the high limit. If its set to 25 psi, thats not much pressure.