Should i be concerned?

Synthia • I am due May 29, 2016 w/Baby #1 ⏳🔜
I am 34 weeks & 5 days pregnant today (4-22-16) I got his approximate measurements back. He is 4lbs 6oz & in the 17% percentile. The OB said that was low. Is this something I should be worried about?! My son is my world I want his growth to be alright.