Was I ever pregnant

So I didn't feel much different maybe abit more nauseous but that's not too unusual for me 😂 but I decided to take a pregnancy test and it came up with a very faint line. Me being impatient I took another and had the same result! So I decided to order some FRER because obviously they're supposed to be the best for early results (by this point I hadn't missed a period) they came through the post the next day and when I took it it was negative so I waited to take the next one till the next morning (when your hcg is usually higher) and once again it was negative 🤔 so I took another strip and again it was positive 🙃 I do know now I'm not pregnant because good old AF is here, but my question is was I pregnant and had a chemical pregnancy or are these tests just not to be trusted