Try it and see if it helps.  If it doesn't, another SSRI may -- some
SSRIs work better than others for some people, and it isn't predictable
which will work best for an individual.  The same applies if it helps
you, but has undesirable side effects.

There has been a lot of bad press about prozac and other SSRIs, but for
many people, they are very helpful, even lifesaving, with minimal or
tolerable side effects.  If they work for you, as they do for most
people, you'll feel entirely normal, but you won't have that descent
into misery you now do.

I haven't heard about a system of taking SSRIs for only part of a
month, but I am not a doctor and not very knowledgable about the
field.  When people take SSRIs for depression it can take weeks for the
full effect to be felt, so you may have to try it for a few months in
order to decide how well it's working for you.

Best wishes to you.  Prozac may make a big difference in your life.
Being miserable, and anticipating being miserable soon again, can skew
your perspective and really drain you emotionally.  You should discuss
your concerns with your doctor, but try to maintain an open mind and a
hopeful attitude about these drugs.