Test flu from test e or c is not common or normal. Test p, test a, or sust yes but not e or c. In my personal experiences test flu symptoms from e or c is your body not agreeing with the carrier oil or too much bb solvent. This is usually accompanied with pip, redness, swelling, feeling weak, and achy.
Being that it's that time of year it could also be that you pinned your glute too close to the sciatic nerve and contracted a sickness too. I've had these symptoms from poorly brewed test e or c before, but it was never accompanied with actual fever.
The list of ifs could go on and on here. 500mg in 2ml as a first pin in the glute. Not deep enough with 1in pin in the glute. (You could have not pinned deep enough and the oil traveled and pooled near the sciatic nerve.) Injection target (sciatic nerve) or injection technique or a combo of both. Poorly brewed gear. Virgin muscle. Plunging the gear in too fast. Pinning too shallow and gear going sub q. It could be one of these issues or a combination of several of these issues.
My advice is to only pin 1ml in the other glute next pin day. The glute is a forgiving spot to pin, but must be pinned in the proper place to avoid the sciatic nerve. Basically draw a cross that splits your cheek in 4 even quadrants. The upper outer quadrant is your target area. Use a inch and a half needle. Plunge the oil slowly at about 20 to 30 seconds per ml. Take a hot shower or apply a heat pad afterwards. Being new to this and having virgin muscle some pip is expected, but it shouldn't cripple.