Ok. You where right. I made a backup of the catalog and photos on my iMac, to be safe when I started using both computers.
For some reason LR was referencing the copy on my local hard drive instead of the external drive... they arre both named the same and contain the same photos so I never noticed what was happening.
Now for the million dollar question. I have the same photos on those two catalogs... some edited on one computer, some on the other and some that where already edited on both. How do I merge them???
How do I end up with all my work in one catalog?? Will importing one into the other work??
And again than you for your help its greatly appreciated, I am new to LR!!