What Are The Chances Of Pregnancy While Switching Between Contraceptive Pills?

I have been changed from Microgynon 30 to Loestrin 20, i was given the new pill during my 7day break and i was told that i could carry on taking my new pill after 7 days as normal ... Will I be protected against pregnancy straight away? On the leaflet it said I should have carried on taking my new pill without a break but doesn't say whether I need a second contraceptive if i did not do this ... any information would be great full