Unexpected possible pregnancy!

Hi everyone. So I’m here again... I’m a mum of 3. I had boy/girl twins just over a year ago and I was late on my period this month. I then came on 6 days late but it was 2 days long and light and then brown, it wasn’t normal for me so I’ve done a first response test this morning and it’s showing very faint positive! 🙈 does anyone have twins and fell pregnant again very soon afterwards? Or have more than one baby under 2 years old! I duno if I can do it... 😫

Also my twins might not be my partners as we split up when I got pregnant plus he had the snip 7 years ago but this baby will 100% be his. Anyone else experienced this. Thanks