Car not wanting to start, lights dim, high RPM but low speed? Please HELP!?

It's an '05 dodge stratus. I usually have problems with the battery, there's also been a clear fluid leaking from my car but all of the fluid levels are just fine. I'm taking my car to a mechanic tomorrow morning, just wanted some insight as to what might be happening. Also, when I take my foot off the gas, the car almost comes to a complete stop. When I press on the gas, the car seems very weak and will only go about 50 mph and has an RPM of about 5