Sediment in wort during cool down

I just brewed a batch of wheat beer using 1.5 lbs of wheat DME for 60 min boil, then added 4 lbs of light DME late addition for the last 15 minutes. During the cool down using icewater in the sink, I am already seeing sediment in the wort separating. This is only my third batch, but I did not see this in my previous two that used some or all LME, and no late addition. Is this normal?

Search for the term "cold break". It's normal :-D

So I just took a gravity measurement from this same batch, and it came up at 1.082. Much higher than the recipe expected at 1.048. What the heck could I have done wrong? It called for 1.5 lbs of DME to be boiled for 60 mins, then 4 lbs of DME to be added late addition for the last 15 mins. I'm not sure that my one packet of yeast is enough to pitch now.

Did you add your top-off water and mix it in really well, before taking the gravity sample? You can't get a gravity that high with only those malts in 5gal.

Yes, I topped off to five gallons. Weird thing is, I took my first measurement less than five minutes after I topped off, and got my reading at 1.082. Then I took one about ten minutes later and it had dropped to 1.070. Do you suppose that the cold break sediment/coagulation that was still suspeneded is now settling and not affecting the gravity as much? In other words, could the sediment increase the gravity until it settles?

how much pellet hops did you use at the end of your boil?

I had only .25 oz for the whole boil, then .5 oz for the last two mins. Not a very hoppy beer at all.

nope..thought maybe you had a ton of that in your sample..but sounds like you didn't.