It looks like you might have experienced condom breakage during intercourse and that horrible experience coming to haunt you and make you think 'extra thin' condoms are likely to break as being thinner than usual condoms.
Don't worry. It is absolutely safe as long as you are using it properly. Just make sure
- that the condom not a tight fit for you
- you don't use inappropriate lubricant (oil based)
- it is still within expiry period