Depo Shot

So I got the shot for the very first time on April 27. My boyfriend and I plan on having sex for the first time (I told him I wanted to wait until I had some form of birth control) in June or July because that's when I see him next. (we are sadly long distance). If I got it April 27, is that enough time for it to take affect and we can have sex without a condom? Please let me know so I don't make a stupid mistake. I really don't want to end up pregnant. And yes I researched it i just want to have personal opinions and such.