I have this boyfriend it was really great until the 3rd week when we just faded apart what should I do to get him to notice me again.

Maybe the bloom wore off. It takes about that long for all the excitement to wear off. He is just not untested anymore. Why don't you ask him if he is still untested. If he is not, there is nothing you can do. Accept it and move on.

You should go to the place you two first met or where you had your first kiss and get it back:) Or have a day where you two just hang out and have fun! :) Just get together with him, if he fell for you once he can do it again:) Good luck girly:)