How long after cramps (ovulating) do you get your period?

I'm not sure yet, but I think I may get my period soon.. I have cramps right now, earlier my lower back aches.. and I have discharge (sometimes a lot, sometimes none at all..) and public hair, and I have a appointment tomorrow that may take a while, and I have been having the cramps sense last night, so more than 24 Hours... and I was wondering... how long after this stage do you get a period? Should I wear a panty liner just in case? PLEASE HELP ME!! :(((