How many days after implantation bleeding, did you get a positive pregnancy test!???

I just had my baby in July of last year. I’m breastfeeding and husband and I do the “pull out” method. I started my first period at 4 month pp. I’ve had two periods so far. And I was suppose to start my period almost two weeks ago. I took a pregnancy test a week ago and it was negative. Then I started spotting a few days ago. I spotted for two days. I’ve been pregnant 4 times (have 3 kids here) and have never had implantation bleeding with any of them. So I’m not sure what implantation bleeding looks like. Anyway, today is day two since the spotting stopped and I took another pregnancy test and still negative. Is it safe to say I’m not pregnant or do I have to wait a few more days!!! I’m scared and do not need another baby!! I feel like we are being safe for the most part, I know it’s not 100% accurate to use this method. I do not want to go on birth control, I just want my body to be normal and husband is suppose to get a vasectomy. That’s what we agreed on and he hasn’t yet. I’m taking a low dose of depression medication, so I don’t want something to be wrong with the baby if I were pregnant and want to stop it immediately if I found out I were pregnant..... her any advice besides the obvious use condoms?? Lol