Mine were more painfull that normal crampy pains, mines were really quite sharp. I have nevr had them in previous pregnancies though and i should say that my last pregnancy didnt show up on a test till 15dpo so the fact that your getting bfns now doesnt mean anything
I was getting pains, on the right side and down below sometimes they were quite sharp was a bit paramoid that it meant something was wrong as i have had an ectopic in the past but now i am wondering if it was implantation pains?
Can I advise that you wait until your period is due?
I heard a really sad programme on the radio the other day saying that those very early tests can sometimes detect what's called a chemical pregnancy which is when the egg has fertilised but doesn't embed for whatever reason so you have a period as normal. The doctors they interviewed said they were very concerned that as these events are extremely common early testing will distress women because they'll think they're pregnant when they aren't really.