It's relatively normal. You may find some more exotic explanations, but muscle relaxation and the release of blood to surface capillaries with this relaxation are probably a factor....

Everything goes numb, and sometimes odd parts ache like my elbows, shoulders, etc.

My  muscles are sometimes sore in general, so that could be a factor. I meditate lying down.

When I meditate, after a while I know I am settling down (at last) when my body begins to experience flooding sensations of expansion, like it is becoming a balloon, the feeling fades, then it comes back, then fades, then comes back in a rhythmic fashion. It makes me catch my breath, it is very ecstatic. Around that time I can sink into the quietness. I do find when beginning to meditate and trying to settle down, I get itches everywhere as I begin to attempt the movement away from the day's busy tension. The itches stop, after about 40 minutes usually, sometimes longer, when the ballooning begins, then I know I am on my way. Vee

I also meditate lying down, it's just easier for me to get completely relaxed.  I have also experienced the tingling sensation you are talking about as well.  In fact today, while I was meditating, I got a huge rush of tingles start from my feet and move it's way up to my head.  Then my fingers started to tingle and the feeling rushed through my hands and up my arms.  I could literally feel energy moving from my feet and hands and up through my body and out through my head.  It feels interesting, but it's best to acknowledge it and then focus back on your breathing.  Meditation bring on a lot of very weird sensations!!