not only this plugin but for any of the plugins I got

Hi, not only this plugin but for any of the plugins I got installed when suddenly I wanted to activate one of them I got this: Fatal error: Allowed memory size of 134217728 bytes exhausted (tried to allocate 30720 bytes) in /home.zakum208/public_html/wp_admin/includes/medis.php on line 1878. I went to that line and I saw no numbers. Pls tell me how to handle.
Thanks!
David R