I would suggest NOT to have nail extensions. They ruin your nails completely and take a lot of upkeep as well. When they get taken off the nails are weak, dry and look horrible. If your nails are already not in a good way I think this will make them a lot lot worse!
What I would suggest is trying Sally Hansen products. I once got one that was a nail strengthener and it made them grow fantastically.
Obviously it's up to you and the extensions look lovely when they have been done, but after a couple of weeks the nails have grown so there is a gap at the bottom and they need filling in. And it takes a long time for the real nails to get back to normal again!
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Sometimes I pretend to be normal but it gets boring so I go back to being me