What’s going on?

So I was due on my period about 20th December I THINK, I took a test 24th and negative, on the 25th I had some really really light pink spotting so just thought I was late, however it just carries on being really light and spotting only, it’s been for 5 days now but it’s been so light that I haven’t even needed to wear a pad and there would only be blood if I put a finger up there to test a bit would come out on my finger, I’ve taken 4 tests but all BFN😩☹️ I’ve been so nauseous and so much acne and terrible mood swings and going to the toilet so often and tired and bad headaches, is it possible to have a really really light period? Or is it still possible that I’m pregnant? Shall I go to the doctors? I really don’t know what to do😓😩🥺