new rebuilt bottom end

[wilsss]

i have just rebuilt my bottom end with new shells and new piston rings. i have ran it for 15min then changed the oil and filter. then took it for a drive for about 20 minutes i used every gear and took 3rd and 4th gear to 4500 revs and deaccelerated to 2000 then did the same in 5th but went to 5000 revs. the car smoked on start up but when i took it on the road i have had no smoke.i have just drove the car then and on the way home it started smoking at the traffic lights and now smokes a little i have only done 85 miles since rebuild. is this normal or do you think something might ne wrong