It's sad to say, but my wife and I can not have a second child, and all because I lost my libido. I think from stress at work, I developed erectile dysfunction. What can you recommend?

Sorry to learn this. The best thing is to see a doctor and I am sure they will make the best recommendation for you

If birth control is used perfectly, it can be 99% effective. Perfect use means that the birth control is used every day at the same time, without any exception. Typical use is how it is most commonly used. It means that the pill is taken at different times or a day is accidentally missed. Birth control, when it is typically used, is 91% effective.

I have read this information from here http://www.pregnancyweeks.org/can-you-get-pregnant-on-birth-control-pills/ where it says there are 4 most common things that reduce birth control effectiveness - Skipping Pills, Taking pill in different time, Taking certain medications and using herbal dietary supplements like St. John's wort

As far as I know birth controls are 99 point something percent safe. Once taken correctly should prevent pregnancy as long as you would want it to. See a link below better explaining how birth controls work:

https://menstrual-cycle-calculator.com/types-of-birth-control-pills-and-how-they-work/

Sorry to hear you are feeling so poorly but nausea does happen to women during the first trimester of pregnancy and for some women straight throughout. It normally starts early in the morning and then the feeling goes away as the day progresses or with anti-nausea medication suitable for pregnant women. You seem to have tried quite a number of ways for relief and have found no relief at all. That must be hard, I hope my suggestion will help. See link below to a number of ways your morning sickness can be relieved.

https://menstrual-cycle-calculator.com/tips-relieving-morning-sickness-nausea-vomiting-pregnancy/

Breastfeeding can hurt especially at the beginning when you have cracked sore nipples that do bleed.

I think a two age gap between both children is suitable and easier to deal with on the body and almost emotionally.

I have come to realize that every pregnancy can be completely different for one person and it is okay!

Breastfeeding is extremely important as that's where all the real nutrients are.

Once birth control is properly used and taken as it ought to be then the likelihood of pregnancy happening is extremely low. Some women have reported getting pregnant while taking birth control but I am sure they must have missed a day or forgotten an injection or for some their IUD might have fell out.

https://menstrual-cycle-calculator.com/getting-pregnant-after-removing-the-iud-mirena/

Just put the baby under his/her receiver when breastfeeding in public. You and baby will be just fine.

Unforunately morning sickness doesn't only last for 12 weeks for everyone, only for some, others experience sickness throughout all trimesters.