Hi Steve..It's not the Sombrero as it is horizontal and your image is a galaxy that is definitely vertical...no actually I am sure it is the Sombrero and I guess it's angle must be because you are down South...kidding just in case you may not be sure.
Those images are a great result first time out and you certainly can be proud of them
.
May I give you my old method of finding PA ..during the day align your main scope with your polar scope so what you have selected is in the middle of the field of view in both scopes..the top of a distant light pole or tree...later at night when set up do a time exposure which will show little arcs such that you can work out where to move your mount to have those arcs center in the center of your image..it works rather well surprisingly.
AND if you find your stars are oval just make your subs shorter and take more...
You have done well and I expect with such a great start it won't be long before you will be helping me rather than me helping you.
Alex