Depo injection

Hi I have 2 children from previous relationship I got pregnant straight away. I am now in a new relationship & have been for nearly 3 years & we have been trying 7 months.. I had my last injection October was due it in Jan this year I never got it I got my periods back about April time there pretty irregular but at least every 6-7-8 weeks 😩 I've had my bloods tested for my hormones & there all fine my partner also has a child pervious. So I'm not sure what's going on.
Has any one else been in this position how long did it take to concive after the injection I only had 2 it's been over a year since my first jab & it's so frustrating. Only took me 3 months after coming of the depo before to concive. Sorry for long post any info or experiences would be great. Thanks ladies ❤️👶🏼