Your questions are deep and thought-provoking. The true answer is quite simple.
There are seven מצוות עשה שהזמן גרמא:
ראייה, סוכה, לולב, שופר, ציצית, קריאת שמע, תפילין.
These seven מצוות are symbolic in nature, and are intended to remind the עושה המצווה of certain עיקרים, or principles, that a Jew must keep in mind throughout his life.
Men need to perform a physical action from time to time to remind them of these principles, because their mind is so preoccupied with the responsibilities and worries of making a living, providing for themselves and their family, defending their tribe against foreign invaders, and so on, that they are prone to forget such basic concepts as ייחוד ה׳, עול מצוות, השגחה, יציאת מצרים, and so on. So הקב״ה commanded them: At the very least make sure to perform certain actions at certain times to remind you of these עיקרים so you don’t totally forget Me.
Women, on the other hand, are given responsibilities which – הקב״ה knows – won’t hinder them from always keeping these principles in mind, so they don’t need these periodical reminders. Obviously, if a woman so pleases, she is free to give herself these reminders as well, by performing the מצוות עשה שהזמן גרמא, and if she does, all the better.
As to your second question:
The main curse given to האשה, was that she would always feel inferior to the איש, even though she bears a more noble task and a more awesome responsibility than the man.
בעצב can be translated “with sadness”.
בעצב – with sadness, תלדי בנים – will you perform the most noble task in the world, the task of giving forth and nurturing life. Why the sadness? Because,
ואל אישך תשוקתך – You will seek always to be like the איש, not appreciating the value that you bring to the world. And as a result of this feeling of inferiority, והוא ימשל בך.
So yes, you are feeling the curse, but the curse is the false perception of inferiority. When you begin to appreciate the value and gift of womanhood, and when you begin to understand that your responsibilities are no less than your brother’s, you won’t feel any curse. You’ll feel blessed.