One depo provera shot and still no period?

I had gotten the shot on may 8, I have had spotting where it looks like I'm getting my period but then i don't. I am not pregnant, I took two tests and they both said negative. Never getting the depo shot again, because I miss my period :( I want it to come back. This is not cool. Don't like it, nope don't like it AT ALL! I mean what every time I get the shot I have to be worried that maybe I'm pregnant? No not going to happen because I refuse to get the shot. PLEASE HELP