Too early?

Kirstie
Last month I had my af on the 21st November but only bled for the one day (was fairly light too). I then spotted a few days later, again just for 2 days. 
Me and my partner have been baby dancing since and today I have felt awful. I've had bad cramps since yesterday evening and feeling sick all morning. I took a test at lunch time but it was negative. 
Was it too early?