My labium is so itchy .... and it

First question: My labium is so itchy tonight.

I scratched it repeatly. During the shower, I suddenly found that my labium
has gradually become bigger and bigger. I'm so worry! How come? Please
help. Thanks a lot!

My second question is:

My period did not come since March 7th. My period used to come steadily
on time. My previous periods came on Jan 4, Feb 4 and March 7. As of today, my period did not come. I've done the pregnancy test for a few times. The result was negative on April 8, then I tested again on April 14 and 21, the results were the same (negative). I don't know what's wrong and I'm so worry!

Please help! Thanks again!

(Chinese response is most welcome)