Breastfeeding and pregnancy

Hey moms

I have a 15 months old toddler who I breastfeed since his first day and by now it's only getting worse. He needs me like every hour, I do understand though, he's teething now and refuses to eat most of his solids. I'm fine with it, the idea was just to give you an idea of how often I breastfeed - a lot.

We weren't planning second pregnancy, though we are not using any contraception. It took 15 months to get pregnant with my first so I admitted it will be even harder now as I'm breastfeeding ( I know you can get pregnant while breastfeeding ) ant were using withdrawal method.

I got my period back when LO was 10 months. Since then I had 4 periods. The average cycle was 35 days. My last period was in October - 13 to 17 Oct.

Today is cycle day 50. A week ago I took a pregnancy test(20mIU) which looked like this

After this one I took a digital clearblue(25mIU) which said Not pregnant, and 2 more first response(10mIU) ( 2 days later and again 2 days later ) and both again were negative. So my last negative test was on Saturday 28 Nov.

Please, if you have any advice or had a similar situation, what could it be? Shall I admit a pregnancy now? I'm quite stressed and have mixed feelings about it.