iphoto transfer

I saved my iphoto library from an old mac on to an external hard drive. I have been adding to it for a long time threw my new mac onto the external hard drive. I just recently moved it from that hard drive onto the computer itself so I can back it up with with time machine. As I have limited space on my mac I cleaned up my iphoto library by deleteing a lot of pictures. First I was wondering even if I deleted them are they really gone? Or are they ony my external hard drive? Secondly when I transfered the libray from the external hard drive to my mac did I also import all of my deleted photos? I'm not interested in slowing my computer down just to be saving some pictures of my pocket. If the answers are yes is there any way to delete them?

Ps. My external hard drive is a WD.

Thank you,