Spotting after ultrasound

Ra
 Went in for my scan today at 21 weeks 3 days. It took a while and she had to use more pressure than normal because our little girl wasn't cooperating but everything was perfect. I started lightly spotting soon after and have been off and on today. I called and they said it was normal but I found it odd since it was only abdominal. Has anyone else experienced this? Anything is appreciated. It's been very light and not constant but I haven't had any spotting the entire pregnancy.