Depo Injection

Hi. I fell pregnant on the implant in October and unfortunately didn’t go through with the pregnancy as it wasn’t the right time, hence why I was on contraception. I had the implant removed and went straight onto the depo (wanted to try something new). Since having the Depo I’ve read up on this and it’s really threw me off wanting to get another shot of this (I’ve only had one shot of depo). After what I’ve read up, I’m scared my periods won’t come back at all or I’m going to be infertile. Can anyone put my mind at ease