Fertilization Symptoms??

I've been trying to conceive for a while.  I just got a great ob.  He did a follicular study and low and behold told me they saw an egg sac in left ovary.  He then told me to go find my hubby.  :-)  Unfortunately he was ill, but we did what we needed to do the next night.  This was Wed. night. Thursday afternoon I had a really bad headache.  I only get headaches during my period.  I figured it was just stress.  Today I've had a few sharp pains in my lower ab/uterus.  At times crampy.  I assume it's too early for symptoms, but was curious if one could tell so soon.  Thanks.