Question about Filling Tilt Trim Oil

I have a 2001 150hp Mercury XR6. When I trim the motor all the way down it makes a noise that sounds like it's in need of fluid. My neighbors front-end loader did the same thing and he bled the system and refilled it and it worked great. So I thought that I'd check my fluid level. I first read through the Seloc manual i have and decide that I must be low on fluid. So I tilted the motor all the way up and opened the fill plug (the white plug on the left side) and oil shot out. Not much, maybe a teaspoon or so.

After that the noise was much worse. So I got the tube of new oil and loosened the plug and tried to add more to the reservoir. I also opened the bleed screw on the lower right side while doing this. I felt like I didn't get any in so I just closed everything back up and now the motor wont go up or down. The bleed screw is closed and the fill screw is closed. I had to use my tractor lift to get the motor tilted up so I could get at the fill screw again.

I'm stumped here. If fluid comes out when the fill screw is opened, then is it full? How do I bleed the system? The manual says this system is self-bleeding, but it can't move to bleed all the air out! What do I do?

Thanks in advance!