Mild positive pregnancy test but bleeding?

Hiya all I'm new to MN, wondering if anyone has had a similar experience:
Period was a week late an admittedly I had been feeling nauseous and fatigued for that week with a migraine which is always a sign of hormonal activity for me. My period came in the end on Christmas eve and am still spotting but something was telling me its not a normal period. Took a test and its faint but definately there line. Am presuming it could be a miscarriage though if so it's a lot lighter than my previous mc. ....
( I have one Daughter whos 21 months and had a previous early miscarriage at 6 weeks. )
Any advice?! Go not open till Monday now