There is another thread similar to this posted by a girl who couldn't get a tampon in all the way. You might want to check it out. To answer your question, though, it sounds like you're not lubricated enough for the tampon (if you try several different ones, it can dry you out and make it painful to get one in). Some doctors recommend KY when you first start using them. Also, the tampon you're using might be way too big -- try the junior sized ones. Another potential problem could be that you've accidentally inserted part of the cardboard/plastic applicator -- you should only have cotton inside you. Remember, when you put it in, you want to push back more than up, if that makes sense. Try standing with your leg up on something -- it might give you a better angle. In any case, don't give up. Tampons are the most wonderful invention and every month I am immensely grateful I don't have to wear a pad (i.e. diaper).