What Causes Pain In Ribs After Having Food?

Hello, about an hour or so after having lunch (had very healthy soup) i have a pain (very intense pain) under my left rib which is intense directly under the rib but radiates down lower and to the further left side as well. I also have a headache as well. I also noticed some spotting (like my period). I had an iud "Mirena" placed back in October....and while my periods are lighter they just come more often and i'm told i'm still inthe beginning stages and it takes time for my body to get used to it. I just don't know if this intense pain is associated with my period or ovulation or if it's something entirely different.