whymwhyme, I'm so sorry to hear that OP! I hear having toddlers is a fun age but can be EXTREMELY EXHAUSTING!
I'm going to address this issue generally, assuming you have both dark under eye circles and under eye puffiness (aka bags)
Firstly, the reason some of us, have under eye darkness, is because it is actually pools of blood that has settled under your eye. When your blood vessels constrict, they become inflamed, when this happens you get under eye darkness. You eyes always look darkest in the morning because while you are sleeping , the blood doesn't have a chance to move which is why we don't start looking our best until early afternoon.
Sleep deprivation is the number one cause of this, however, too much salt causes fluid retention which can increase puffiness and darken the under eye area. There are a slew of other things that can be the culprit, but from reading your post, I am leaning to these two.
NOW THAT THE BORING STUFF IS OVER< HOW TO DEAL WITH IT!!!! FINALY!!!!
*For puffines I would use any tea both the caffeine and the tannins in it will help to reinvigorate the calm down inflammation. Make sure to heat 2 teabag (I like chamomile), in a cup .Once they are heated take them out. Pour the water out and place the tea bags in your cup to chill in the refrigerator for 4 minutes. Take the tea bags out and find a nice big chair, sofa or bed to rest comfortably. Squeezing the excess tea out, with your eyes closed, gently place each tea bag on your eye for 5 minutes. Try to do this every morning. If not possible try 4-5 a week or night before or morning before you go to a special event.
Eye cream. It is important to use an eye cream that specializes in puffiness and dark circles. Many of them have caffeine and some have mica (if you do not have a mic sensitivity) The best approach, if feasible, is to use a serum under the eye cream so the eye cream may bind to the cream thus making it more moisturizing. Make sure to buy a an eye that has an humectant in it, as humectants draw moisture from the air.
If, I remember correctly your eye area, is 3 times thinner than the rest of your fave, thus it is imperative that you use an eye cream made specifically for the eye are and not something like a face moisturizer. You only need to use the size of a pea. Also make sure to use your weakest finger on your dominate hand which will be your ring finger. just pat along your eye area, making sure that you are not to close to the lash line. The simple act of doing day to day things will ensure that your eye cream will creep where it needs to go. If you go to close to your lash line you make burn your eye or make your vision blurry and irritable. Do not forget your ocular bone, as this will help to keep that part of the eye moisturized too.
Next, you are going to want to invest in two concealers. One in a pink or yellow shade. If you have porcelain skin, you will want to choose pink. If you have olive skin, you will then choose yellow. Very gently using your ring finger, dab the coloured concealer underneath the eye and up to the ocular bone. You can use a brush or beauty blender for this, but I have always preferred to use my hands.
Next use a concealer that is 1 to 2 lighter in shade to use under your eye. Pat, Never pull. Pulling creates wrinkles. So pat and blend using a beauty blender or brush. Make sure that all of the coloured corrector can no longer be seen.
Proceed with the rest of your foundation.
Lastly, use a highlighter stick or Spotlight, from Clarins and dab a pea size amount to both under your eyes and on the inside corner. Use on your ocular bone as well.
Continue the rest of your make up regimen.
Please note that this plan is only for eye concerns many caused by sleep deprivation or too much salt in your diet. It does not cover hyper pigmentation/melasma or other medical conditions. This is just information that I have studied working in the cosmetics industry for almost two decades. I am not a doctor and do not claim to be. For entertainment purposes only. I am semi-retired a no longer work in the cosmetics industry and am not being paid in anyway for my advice.
Just saw a fellow mums netter, in need!
Good luck! 