Bob Martin flea tablets??

[tulipflowers]

Got a 8 week old kitten 2 days ago, realised she had fleas last night, administered a flea repellant, but still there today.
Have just given a bob martins flea tablet, she is scratching like mad :-( says from 4 weeks, but have just googled the tablets, they seem really bad.
Have I done the right thing??

I've only heard bad things about them I must admit. How is she?

She stopped scratching after an hour, was really scared, def will not be using them again!