Thanks for your Query,
You should continue to take your old or new pills along with spermicidal condoms that is a first requisite.
I would like to suggest you a safer sex method that will help you to reduce your paranoid.
First you understand that pregnancy
occurs due to contact of ovum of female & sperm of male.in a regular period female having 28 days cycle ovulation takes place on 14 th day of cycle.Now the male sperm can live in your body for 2-3 days & your ovum can live for 4-5 days.So if you have a sex on 12 th day of your cycle to 18 th day of your cycle then & then you only gets pregnancy.To be more safer side we should add 2 days on each side so if you have a sex on middle 10 day of your cycle then you get pregnancy.
So enjoy sex for first 10 days of your cycle & last 10 days of your cycle without any fear of pregnancy.