Faint test!

I put my test on here 2 weeks ago with a vvfl and got told positive I've had some complications not knowing what to think I've been to doctors paid for a early scan they couldnt pick anything up from the ultrasound scan yesterday, took a test when I got out the scan and was positive again faint line but can see it well! I'm counting that I'm 3 weeks and 2 days pregnant would I have been able to see anything on a normal ultrasound scan or would I need a internal?