Ongoing spotting early pregnancy

Hiya, just looking for some help/advice...

I am 4 weeks pregnant and 2 weeks after sex I had some bleeding for only 3 days.. I thought it was a period as in the first day it was dark in colour and relatively heavy. But it died down to some light pink spotting and ended. Anyway two weeks on I have now started to have some light pink spotting again .. but it only comes out when I wee, I think maybe due to the pressure? And also just from when I wipe just a mark on the tissue.

I have heard of implantation bleeding but I didn’t know it was ongoing.

I’m just wondering whether this is quite normal?

And whether anyone has lightly bled like this during their early stages of pregnancy?