Really worried and confused,please help!

Kristen
Okay so went to ER last night to bleeding and pain,had blood work and ultrasound,based on my lmp I should be around 9 weeks,but the ultrasound said 6 weeks 3 days and they said they couldn't measure my baby as it was still too small,but they said they hear/saw a heartbeat. I'm seriously confused,could something be wrong?