Yes, sleeping with contacts can cause headaches. Since sleeping with contact lenses can increase the risk of severe eye infection, and if you wear it overnight, there will not be enough oxygen getting into your eyes, thus your eyes can get dry. Also, you eyes can be hurt by the lenses, and your nerve will be affected, all these can lead to your headaches.
It depends. Usually, most of contact lenses are not allow to wear when you sleep. If you wear it when you sleep, it cay cause many eye problems such as dry eyes, itchy eyes, eye pain as well as headaches. But i heard that there is a type of contact lenses that allow to wear when you sleep. Also, there are also contact lenses that can be continous wearing for a mouth. If you often wear contact lenses, you can choose such contact lenses. You can google it.
Yes, your sleeping in contacts will cause your headaches. Wearing contact lenses during sleep will be so bad for your eyes which will let your eyes get infection easily. You could do the warm compress to release the eyes. You should not do this again which will be so bad for the eyes the next day.
Exactly, your headaches may due to your tired and muscles relaxion. Just a whole night wearing contact lenses will not be possible to cause headaches. But pain, redness in eyes just due to your contact lenses. After a long time tiredness and fatigue is easy to lead to headaches and pain in body. Warm tip: have a good rest and keep a reasonable working time are good for your health.