I'm not too sure Sarah... have you had your 6 week 'post birth' checkup yet? Maybe you could ask your Dr?
I guess its different for many women as well maybe depending on their birth experience?
I was too afraid to use tampons for ages.. months and months... but that was due to having some painful grazing, which really just put me off wanting to go 'down there' unecessarily.... even after it had all healed!

Sorry I can't be of more help....