This is really the only group I ever get responses in!

My period is due Feb 5th.. so 2 days. I've been having brown discharge since 1/30 and yesterday it was a little hint of light pink. I've been feeling slightly nauseas and extremely tired so I tested yesterday and it was negative. I should have ovulated between the 19th and 23rd.. I have very regular periods. Is it too late in my cycle to have IB or is it a possibility? Does it just sound like spotting before my period?