cramps and spotting!!

last night i began cramping and spotting. the blood wasn't so light which led me to rushing to the hospital out of panic. the dr. did an ultrasound and told me everything was healthy. i heard the heartbeat and saw the baby at 6weeks and 2days. my blood and urine results came back good. plus, i stopped spotting. it is now light pink when i use the restroom. although, i was told that everything looks good so far i am still a bit worried. have any of you experienced this before?