Smoke on cold startup and continuous smell

Hi all,

I have recently changed my car's oil at a mechanic (not the usual
place where I change it)...and didn't really ask about the type of oil
or its grade after he finished the job.

I find now that every time I start the car in the morning, a huge
cloud of a blueish tint smoke (which is oil burning) rise..and the
cloud is really big! I'm ashamed to turn on my car when there are
people on the street waiting for the bus.

The car is a 1996 Honda Accord (4-cyl, automatic) and this is the
first time I notice this problem...however the cloud of smoke
disappears when the engine warms up.

Today (after about 2 weeks) I wanted to check the oil level to make
sure there is a little bit left in there...and to my surprise when I
pulled the gauge (before I start the engine), the oil level was about
3/8 of an inch above  the upper limit.

Do you think that is the cause of the smoke and if so what should I
do? re-change the oil or take the excess oil out? will there be a lot
of harm done on the engine now?

Thanks in advance,