PHP problem with plugin?

I wanted to install a plugin that was bigger - so I made my research to increase the upload file size limit. I've read to look for php.ini. I did create one, insert lines. Did not help, I got the same issue, could not install the plugin I wanted.
I looked for other solutions, wp-config, user.ini, installing plugin, and somehow I managed to do it.
But now, I unstalled BackupBuddy plugin and it gives me error: "Sorry, you are not allowed to access this page." I believe this could be related to PHP issue? I have MultiSite installed, and I can not see the BackupBuddy plugin in my dashboard, only on MultiSite, Network view dashboard where I have a "backu now" button that gives the error.
Could you please check if I edited some files that can cause this problem, or if not, what else?
Thank you!