I think im pregnant again !

I have a son who will be 4 months in 4 days and I was on the shot but failed to realize it was time for a new shot and was having unprotected sex I had my period 2 weeks ago and just yesterday I had what looked like implantation bleeding I have been feeling nauseous and tired just like I did my last pregnancy I’m going to the doctors tomorrow to take a pregnancy test and I’m just hoping I’m not pregnant again I’m not ready but if I am I will of course take responsibility for my reckless actions anyways my question is can anyone give me some advice or peace of mind or do you have any kids close in age and how is or was it p.s if anyone is religious could you pray for me that I am not because even tho it will be a blessing I’m seriously not ready !!