ultrasound

What is the earliest you can for sure see a baby on ultrasound ? 
Would 5 weeks be to early to see ? 
There is this place where I live offers 2 free ultrasounds since I still don't have insurance to make my prenatal appointment I want to go get the ultrasound but since I'm barely 5 weeks I don't want to get stressed out if they don't see the baby 
What do you guys think should I wait a little longer ?