9 weeks, brown discharge

Theresa • Been with husband for 7 years; married this September in Tahiti (!!!!) TTC for a year, preg 1 month after wedding!!
Got some spotting tonight. I've had brown spotting before, at around 5 wks and it was nothing. I saw my US this morning and all was healthy. 156 bpm heartbeat, little lim-buds moving about. But tonight I saw brown discharge in the bathroom - not period heavy, but heavier than I had at 5 wks. It's coupled with light cramping, but in all honesty, that could be gas. 
Has anyone else seen this at 9 wks ? Should I be concerned ? If it wasn't Saturday, tomorrow, I'd call the doctor.  Just worried.