Is this a faint positive line?

We have a 23 week old baby and I fell pregnant whilst on the pill in April last year. Since giving birth the only contraception we have been using are condoms. My periods returned when our baby was around 10 weeks old. I track my periods and they return like clockwork, I always wake up on that morning and realise I have started. My period was due today and nothing, I never experience PMS so had no inkling.

When I first fell pregnant last year, I completely went off alcohol, no other symptoms, no implantation bleeding - nothing. I had a tiny tiny tiny tiny bit of spotting 2 days ago but I assumed I cut myself from shaving, that’s how small it was. I have completely gone off green tea and I usually drink this daily. I have been vomiting during the weekend but that’s solely because I had a virus. Unsure if I have swollen boobs as I am breastfeeding so they do change appearance. I did a pregnancy test at around 12pm today and was relieved to see a negative result. Upon looking at the test 9 hours later, I am adamant I can see a very faint line, I haven’t told my partner nor anyone else yet so I don’t want to ask anyone if they can see anything.

I will test again tomorrow if my period hasn’t started and if it’s negative and my period is still delayed after 7 days from today I will test again but what do you ladies reckon? Thank you!