You need to go see a heart specialist. It sounds like your body is not getting the proper circulation that it needs. That sounds like what is causing you to black out when you stand up. Having cold hands and feet is another symptom that you have poor circulation.
It sounds like you have low blood pressure and anaemia. Try an iron supplement to start with, when you go to get up, get up slowly and a bit at a time. You do need to see a doc just to rule anything else out. Get yourself a good B complex vitamin and take one a day. Your period will deplete you of many things.
Definitely get blood tests to check hemoglobin and ferritin (iron stores) levels, along with Vitamin B12, magnesium and Vitamin D3.
I was dizzy, fatigued, etc due to anemia, iron deficiency (you can have iron deficjeny and not be anemic), and low Vitamin D. I did not test my magnesium or B12, but believe they're are also low. I received a blood transfusion. I take supplements to raise my iron, D3, B12 and magnesium levels.
I have not re-tested my iron yet, but my Vitamin D went from 19.2ng/mL to 61.0ng/mL in 11 weeks. I'm not extremely dizzy and I don't pass out.
Complete Blood Count (CBC)
mean corpuscular volume (MCV)
mean cell haemoglobin concentration (MCH)
Total iron-binding capacity (TIBC)(IBC, UIBC)
Red cell distribution width (RDW)
*can reveal mixed iron and vitamin B12 deficiency as this results in red cells of variable size*
B12 levels checked, not just serum B12 but HotoTC levels as well as MMA and Homocystein.
B12 deficiency can cause depression, anxiety, fatigue, weakness amongst other things.
Vitamin D test:
The only blood test that can diagnose vitamin D deficiency is a 25-hydroxy-vitamin D (25 OH vitamin D). Unfortunately, some doctors are still ordering the wrong test, 1,25-dihydroxy-vitamin D.
have your Doctor do a Magnesium RBC test. It's not a standard test drs run, but the only accurate blood test for magnesium. Magnesium serrum which most doctors run is not accurate.But make sure it's a RED BLOOD CELL magnesium count. Looking a plasma magnesium levels is probably a waste of time.
Sounds like Positional Orthastasis with Tachycardia Syndrome. Find an electro-cardiologist and get a tilt table test. It will either give you a diagnosis or rule out some important stuff. Good luck!