Adderall and restlessness

I am 21 years old and my doctor prescribed me 20mg of Adderall to take twice a day. I've been taking it for about a week (only in the morning, I'm still too wound up to take it 4 hours later!) and I have already lost 10lbs. Also I've been having trouble breathing deeply, chest pain, tingling in my arms and legs, and no appetite whatsoever. Are these symptoms normal?

I am taking Adderall for the first time today, for ADD-like (inattentive rather than hyperactive) executive function symptoms resulting from a brain injury (frontal, especial left frontal, and temporal lobes) I sustained 8 years ago. I have had extremely bad problems with productivity ever since. I am a twentysomething female, 5'8" and 135lb and I took 10 MG an hour ago. I would say I am feeling unusually alert for this time in the morning, senses feeling more "awake," my heart rate a little elevated but not too abnormal, and also in a particular sense feeling calmer/less anxious than ordinary. I feel less compulsion to websurf, which is something I have a serious problem with. I'd say I am also finding it easier and smoother to compose this writing than I would ordinarily, I am hyper-literate and have a strong desire to write, but writing is usually like pulling teeth--very slow and very hard to organize my thoughts. I am starting to feel a buzz; I find a caffeine buzz very unpleasant and distracting, and caffeine doesn't seem to help my attentiveness and productivity all that much. But I am more alert and focused, and that part feels good. It is so tiresome and frustrating feeling "lazy," unfocused, foggy, and restless like I normally do. The buzz I am feeling is getting a little more intense and my heart rate also up a little more, I feel kind of tingly. I kind of don't like it and time will tell how much it bothers me after I am more used to it. I suspect that I may find it a reasonable trade-off to feeling focused. And again, in a particular sense I feel more peaceful than normal because I'm not having the stray thoughts and spacyness I normally do. That feels like a relief. I think I can see why people eat less on this drug, because of the heightened physiological state and the reduced feelings of boredom or restlessness that often drive people to eat. If I can use it to eat less sweets that could be good, but I will try to be careful to keep eating regular healthy meals. It's now an hour and a half since I took the pill and I think the effect is perhaps plateauing. My sinuses feel very clear and my mouth is perhaps a little dry. I was a little afraid to take this thing but the buzz feeling is probably not quite as bad as I feel after a 12 oz cup of black coffee and much less bad than a bad dose of nighttime cold medicine I had once, and with more benefit. I'm going to leave this posting at that and see what more I can get done today. Hopefully these observations help someone.

To the 15 year old wondering whether he/she should take Adderall, this is something you can/should ONLY decide together with a doctor. The doctor will be able to give you much better advice than anyone on the internet. Seriously. But if it puts your mind at ease any, you should know that underweight, unless it is extreme, is not in itself a serious health risk. If being underweight makes you self-conscious that is also a consideration, but a doctor can probably help you somewhat to manage your weight whether or not you take a stimulant.