Mens Conditions Forum - creatine side effects

I am a male, in my early 20's, 5'9" ~145lbs with no history of health issues.

Last week I decided to get back into working out after about 2 years off. I headed to GNC and purchased a can of "Cell-Tech", and a box of "Nitro-tech". The Cell-Tech is a creatine supplement which also contains the following ingredients:

- lab-grade dextrose, citric acid, calcium silicate, natural and artificial flavor, modified food starch, gum arabic, titanium dioxide, tricalcium phosphate, xanthan gum, fd&c red no.40.

The Nitro-Tech is basically a protein shake.

I was to take 2 scoops (or 100 g) of the Cell-Tech (creatine) every morning, and directly after workouts for 5 days, and the Nitro-Tech just after every workout.
A few days into my program my left arm (between the bottom of the end of the bicep and the elbow) had become swollen. It freaked me out a little because it didn't hurt (only the expected soreness after working out), no discolor, and I know I didn't push myself that hard. Well, the swelling went down in that arm.
Two days later I noticed that the outer (right) side of my right forearm had swollen, from about my elbow to 2/3rds the way up (not near the wrist).
The swelling does not have any pain, it is puffy, and from what I have read online it sounds like pitted edema (if I push on it for 5 seconds it will leave a dent).

I recalled bumping my right forearm on a desk, not hard enough for any real injury, but perhaps hard enough to bruise slightly. So I thought this must have something to do with water retention in my muscles from the creatine, I decided to hit my other forearm with my right knuckle, not hard enough to hurt myself, but just as hard as when I had bumped into the desk with my right forearm. I thought if this swells up I know that it is from the bump, and not just some random occurrence.
The next afternoon I noticed that my left forearm, right around where I hit it, had in fact swollen.

The left arm's swelling (which was never pitted, by the way) has seemingly gone away, the right and left forearms swelling have not gone away, and both have pitting. The right forearms swelling has been around for ~2days, the left for a little over 24hrs. I can't tell if either have gone down at all, but they are still obviously swollen.
The swelling in either has never been huge, but has been noticeable to myself and others.

My theory is that the creatine which is supposedly known to cause water retention did exactly that (retained water in my body), and when these minor injuries happened, it (aggravated, popped, something?) and water began filling into the muscles around these areas. Of course I really have no clue what I'm talking about, so maybe someone here (hopefully a doctor) can help me.
I can't seem to find anything similar to this in google searches.

Working out, and Creatine supplement are the only new introductions to my life. No drugs, no medications, don't drink/smoke, have always had a clean bill of health.

Any help is greatly appreciated.