1. We don't say that our hair explodes. Not in American English anyhow. That sounds like a bomb went off. :) I think what you mean here is what we call "having bedhead" in American English. This is what happens when you go to sleep and in the morning your hair is a total mess when you wake up. Here is a photo of a woman who has bedhead. http://static.guim.co.uk/sys-images/Education/Pix/pictures/2012/12/19/1355913782904/young-woman-woman-in-bed--008.jpg By the way, they actually have a product called "Bedhead" too which I have never tried but I always see in the stores. Hehehehe Here is a photo of it. Maybe you could try it? I don't know. :) http://vonwhairproducts.com/images/bed_head_re-energize_conditioner.jpg A related phrase though is "standing up on end". This is when your hair stands straight up whenever you get shocked by electricity or you are frightened. So an example sentence would be: "He was so frightened that his hair stood up on end." Here are photos of both a girl's and a guy's hair standing on end from an electric shock: www.muscogeemoms.com/wp-content/uploads/2013/03/hair_standing_on_end_small.jpg http://cache3.asset-cache.net/gc/104303328-man-holding-jumper-cables-gettyimages.jpg?v=1&c=IWSAsset&k=2&d=vMmHHO507JZyKjDPJ1346wbFJ8fYo6cutLrd%2BiAqE8E%3D Here is a cartoon of a guy's hair standing on end because he is frightened: http://www.clipartguide.com/_named_clipart_images/0511-1008-1201-0059_Frightened_Man_Gasping_with_His_Hair_Standing_on_End_clipart_image.jpg By the way, when the hair on your arms stands up because you are frightened from a scary movie, etc, you can also say it is "standing on end." So it doesn't mean just the hair on your head. :)

-My hair ended up exploding last night. -I have a habit of using my headband which keeps my up-do in place. -I guess that's why I have a migraine-like headache. I WAS WONDERING WHY YOU ARE ALWAYS WEARING THAT HEADBAND!!! :)

I don't think an English speaker would say the first sentence. 2 reasons - 1. exploding is not correct 2. you are talking about sleep not night - unless you are very unusual :-) -My hair has been exploding at night. Perhaps "My hair ends up going crazy during sleep" -So, I have a habit of using my head band which keeps my messy hair pulled away tightly from my face. *(I wanted to use this word 'updo' in this sentence. How would you say?) - I don't think that your hair is naturally messy, that is something that happens at night. I don't think updo is a word - do up is the phrase. so perhaps " I have a habit of using my head band to do up my hair and pull it away from my face during sleep." I added "during sleep" because that is what I think that you intended. -I guess that's why I have a migraine-like headache. (Good sentence !)

2. I don't think you can use the word "updo" here like this. An updo is defined like this: An updo is a hair style that involves arranging the hair instead of allowing it to fall freely. It can be as simple as a ponytail, but is more commonly associated with more elaborate styles intended for special occasions such as a prom or wedding. So an updo is usually a very pretty and elaborate hairstyle. Not just pulling back messy hair with a headband or a rubber band or something else. They do mention that it can be a ponytail but I think they mean making a nice ponytail and not just putting it up quick because you have bedhead. Know what I mean? My mom was a little confused too. To be honest, I had to ask her how to use this because I never use this word ever. She said it sounds like you are just pulling or pushing your hair back with a headband. She said updo's are more elaborate too. :) Anyhow this is a photo of an updo. See how elaborate and decorative it is? http://www.syerasite.com/wp-content/uploads/2014/03/Wedding-updo-hairstyles-4.jpg I would just say this: "Whenever I have bedhead, I typically just pull/push my hair back with a headband (to keep it in place / to keep it out of my face)." or "Whenever my hair is a mess in the morning, I typically just pull/push my hair back with a headband (to keep it in place / to keep it out of my face)." For the word updo... You could maybe say something like this: "I like styling my hair in an updo whenever I go out to a nice restaurant with my friends." -I guess that's why I have a migraine-like headache. Perfectly correct. :)