"my pixhawk will only army whe I pull the right stick to the bottom left."
that's because your RC control channel assignment is messed up, likewise, your motor connections are too, causing the flipping.
read and follow documentation.
What mode is your Tx?
I'd suggest rechecking the radio calibration section, verify that the stick you are using for throttle moves the throttle. Check that each of the other sticks move the bit you are expecting and in the right direction. If not then fix that.
Then I'd also use the motor test (with no props) and verify that each motor is correct.
Go back to the start of the setup procedure. Your machine is behaving very strangely. Have you gone thru all the required setup steps or have you simply put the hardware together. You need to upload quad firmware to pixhawk before any settings. Follow the the wizard in Mission planner in the Initial setup menu. Failure to do this will result in your quad not being flyable.
Check Mode 1 and Mode 2 of not only your radio, but what is selected in QGC or whatever you are using.
Mode 2 is generally used in the US. It is easy to tell: the left gimbal on your RC unit doesn't spring back to the center when pushed up. This is throttle. In Mode 2 the arming procedure is bottom right to arm of the throttle gimbal.
It sounds like this is where you have something wrong - between hardware and software config.
ESC calibration: there are so many ESCs with so many variables out there. What ESCs are you using?
The drift in stabilize can be caused by two factors. You need to ensure your model is balanced correctly around the COG, move the battery to achieve this. Also the gyro calibration can cause drift. place your model on a level surface and view the heads up display in the flight data menu in mission planner. the roll and pitch must be perfectly level. The loiter drift is more likely a compass or GPS issue. Is the compass head pointing in the correct direction in the flight data mode. Remember the compass heading will be offset by the true north amount in your area of the world.