K.T.
M.,
You will no doubt get plenty of responses regarding the hormones and menopause, etc.
I want to tell you that I am so sorry for your loss in March/April. It is clear from your post that you want to have another baby, and when you are pregnant, (planned or not)...and have positive feelings surrounding the pregnancy as you did, you wanted THAT baby. ( I have had 5 miscarriages in the mix of having 3 children myself).
I urge you to make sure you take some steps to really mourn the loss of that baby and what that loss really meant to you. You say that you feel like you failed your family, your boys, your husband...etc. But, in the same time, it was NOT your fault. People may say, "that baby was not meant to be", or "at least you have 2 healthy boys", etc..they do NOT know what to say. You found out you were pregnant, and you wanted THAT BABY, and built dreams for THAT BABY. So allow yourself to grieve for that baby, and figure out what you will say to your son if he asks about the baby that takes any responsibility off of you.
Next, you are feeling alot of anxiety regarding your "time" crunch and irregular periods. If you truly desire to get pregnant again, you should see a fertility specialist for advice. They can help address your irreg. cycles, and tell what they recommend for you. Don't mess around waiting 3 months for another cycle. Not if this is what you truly want.
Good luck to you, M..
God bless you and your family this and every day!
K.