It sounds like you are probably dealing with a variant of premenstrual syndrome, which is a complex of symptoms that many women experience before their periods, just like you are describing. These symptoms may occur due to the changes in hormones that occur prior to the period starting, which have multiple effects on the body.
Bloating is by far the most common symptom of premenstrual syndrome. This is often easy to control. In particular you can reduce it by avoiding salty and processed foods around the time when the symptoms tend to come out, as well as drinking lots of water and clear liquids and getting plenty of exercise. You many want to take an anti inflammatory medication like ibuprofen if the bloating is uncomfortable and if your doctor
recommends it. The constipation is probably related to decreased fluid intake and lack of activity caused by the other premenstrual symptoms. Therefore, if you can stay well hydrated and active, this should improve a lot also.
You should also talk to your primary care doctor
or your OB GYN doctor to make sure there is nothing else going on. If the premenstrual syndrome symptoms are very severe and do not respond to these simple sorts of tricks, there are also medications that can be prescribed.