it's ur sciatica hun like these girls said as well...take a warm bath or try and massage it out some..it will come and go thru the pregnancy..

agree with @hermommy. my sciatic acted up bad in the beginning where I about cried to stand from sitting or bend over. It lasted several days to a week and eventually went away. As for round ligament pain that too lasted a while and still comes and goes when belly is growing.

yes it's a thing as for the back pain sounds like sciatic