You didn’t re-pull it, it was already pulled what you should do is R.I.C.E. (Rest, Ice, Compress, Elevate) 2 days is not long enough of a period to rest a injured quad. Do R.I.C.E. and do some quad stretches 1-2 times a day. You don’t have to stop working out just stay away from leg days for a little bit and jump on the bicycle take it nice and easy.
I really can’t call it remember I’m no doctor but my first question is how much water are you ingesting second what did the doctor say your creatinine levels are? The reason I’m asking is because the more you drink whey protein and the less you drink water your creatnine levels are going to increase and that’s going cause your “liver or kidney” failure. So the more you ingest the more your creatnine levels will increase and will stop your kidney’s from working properly. And think its more so kidney than liver. Now you can take your doctors opinion and stop drinking the whey protein or get a second opinion. But take all I say with a grain of salt. I hope this helps.
That head rush/dizzy feeling you get when standing up to quick is called Orthostatic hypotension. Its caused by a drop of blood pressure where the blood begins pooling in the lower extremities. Orthostatic hypotenstion is quite common in a lot of people but most prevalent in the elderly.