1. My leg is asleep.

2. My leg is numb.
3. My leg is sleeping.
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Does #1 mean #2?
Does #3 carry the meaning of #2?

4. My throat feels funny.
5. My throat feels strange.
6. I have an itchy throat.
7. I have an itching throat.
8. I have a weird feeling in my stomach.
9. I have an irritable weird feeling in my stomach.
[Which ones are similar to #4? Do you have some more similar expressions? Thank you.]

1, 2, 4, 5, 6, and 8 are all fine. The other expressions would not be used.

Yes, 1 means 2.

And 5 and 6 mean about the same thing as 4.

(headache) My head is pounding. My headache is so bad, I need to darken the room and go back to bed.
(arthritis) My knees (or hands or neck or ??) are just killing me; they really hurt today / they are very sore and aching today.