Ultrasound measuring behind, can I catch-up!?

SpringBaby
Just had an early ultrasound (UK so had to go private & paid £79). Should be 8 weeks 6 days but measured 7 weeks 6 days, really strong heartbeat so all fine but I feel so cheated being pushed back - I've really been suffering with exhaustion & sickness I just want the first trimester over with & to get to the magic 12 weeks. Anyone measure behind & manage to 'catch-up'? Xxx