Line still faint 😥

Nicola • I`m a 32 year old teacher from the UK. Had my rainbow baby in September 2017 after miscarrying twice. Had a chemical pregnancy in January and now TTC #2
I had a BFP on Sunday which was faint and it's still faint now. I've only used the cheap strips but they don't seem to be getting any darker. And I don't feel any different at all apart from having sore boobs. There is no sensation in my belly at all, no cramps or anything which is making me worried. I miscarried in March and don't think I'm going to get much further this time 😩 Help greatly appreciated xxx