I found out mon. i was pregnant. doc. confirmed it. nothing is showing in the ultrasound. is something wrong? i'm 5 weeks.no symptoms. no weight gain

Not necessarily: 5.0 weeks is about earliest time that one might expect to see findings of a pregnancy on a transvaginal ultrasound. That nothing was seen doesn't necessarily indicate that something is wrong, as dating by last menstrual period can be inaccurate. I would get a repeat ultrasound in a week. If you have bleeding, unusual pain, etc. then I'd recommend going to the ER.