Were you nervous about something? When we get an adrenaline rush due to excitement, nervousness or anxiety, all the blood rushes to our organs and away from our limbs making our skin feel cold and clammy. Normally you end up taking small quick breaths and very deep ones which makes you hyperventilate. Hyperventilation will cause numbness. I made myself hyperventilate once at the age of 10 to the point where I couldn't walk anymore because my legs were so numb. I have had GAD my entire life due to a minor heart valve defect I was born with (MVP), so I know all too well about what stress can cause.
If this occurs frequently, you may want to see a doctor to rule out hypoglycemia, diabetes, heart problems, or poor circulation.
Cold feet and hands are normally just signs of poor circulation or low blood sugar. Both are pretty common. If you feel numbness, that's when its cause for possible worry. Pay attention to whether you "warm up" after a meal (which means you're not eating frequently enough or your diet is lacking complex carbohydrates and has too many simple carbohydrates that break down too quickly).
If your cold feet doesn't revolve around meals, try exercise and cold showers. People who sit or stand a lot tend to have reduced circulation in their legs. Don't cross your legs either. If you have dark varicose veins or spider veins in the legs or feet, that's also a sign of poor circulation in the legs.
I will also add that Anaemia can cause similar sympthoms .I have mild genetic blood disorder which leads to anaemia .My feet and hands are always cold but in general i have low body temperature .Other signs are pale skin ,fatigue ,dizziness and weakness .It also may cause numbness in limbs .Check your vitamin and mineral levels .You mayneed to increase intake of vitamin B 12 and Iron in case that anaemia is presented after medical check .I will advice you to contact your physician for any case .