Conception isn't exactly something you can plan for a specific month. If it happens, it happens.
I agree with Joy, you can't really predict when you'll get pregnant. Just calculate the time where you think that you will be most fertile during your cycle, have sex regularly and hope for the best. Make sure you start taking prenatal vitamins and Omega 3 supplements 3 months before you get pregnant so you have a healthy uterus and ovaries.
Good Luck! Oh and...even with the most perfect planning, it never works out the way you planned it, so just be flexible in your expectations.
I agree with Joy and Mumita! I hate to break it to you, your plan may not go as expected. Even with proper timing, ovulation kits, tracking temperature and etc, it took my husband and I two years to conceive our first child.
As for having an abortion I cannot comment on that, because I have nothing nice to say about that choice. As for the Depo, sometimes it takes a woman a few cycles to get her body back on a normal routine.
So, if your plan works consider yourself one of the lucky ones, if it does not consider yourself one of the normal ones!