Thank you for your email. I understand how frustrated you feel and how you feel you never have time for yourself. Because you are away from your girls most of the day, they want to attach to you the moment they see you. They need to feel close and attached to you. It is imperative that you meet their needs the moment you see them for an hour or two. Drop everything else, and give them 100% attention without being irritable. Really try to enjoy this special time with them, and then hopefully you will have more time for yourself later on.
While 'calming tablets' will help they are not a long term solution. Try to manage your time better, so you can have time for yourself as well.
Do an autopsy of your job, to determine if it is really what you want to be doing. Is it making you feel fulfilled or is it adding to your stress and irritability. Chat to your boss about flexible hours, and or changing your job. Getting you an assistant if you need one.
Try and organize a relaxing activity to do during your lunch hour. It may be a yoga class at the nearby gym. A walk in a park. A lie down, even if it's on your office floor. Listening to classical music.
Ensure you are eating well and getting enough exercise. Take an hour a day before the children wake up to exercise or meditate. Just sitting quietly and day dreaming will help to relax you. Concentrate on breathing deeply.
Also ensure that you get enough rest. Try not to work and do chores at night. Find relaxing activities to do when the children are asleep.
Organise an hour or two on a Saturday where you take time out from your busy schedule to do something you enjoy doing. Get dad, a family member or a friend to babysit. Ensure you spend the rest of Saturday with your children engaged in fun activities.
Plan a fun family activity that is relaxing, like a picnic on a Sunday. Being in nature is restorative and relaxing. Make Sundays family fun day when no chores are done.
Find a counselor, church leader, someone you respect to chat to about your feelings.
Your time with your children is short and precious. Try to enjoy them by organizing fun activities to do together.