Q: White smoke from exhaust, pretty sure its not head gasket?

So, one day i went to check my oil and coolant and they were both low, so i used my other car to go get the products to top them up, using both permite (thats what last owner used) but i wasnt sure what oil they used, there was 5-30 but there was also 5-40 which recommended using if i was putting 5-30 in it. so i put the 5-40 one in anyways thats not the point of the story. the point is afterwards i went to the petrol station to get some fuel and as i was stopped at the lights on my way out white/grayish smoke just came out of my exhaust, as soon as the light turned green i took off and parked to see what was going on, and it stopped? but now every time i drive my car and i stop at a red light or something it smokes, at first not so much but as im sitting there idling it gets worse. It does stop after ive stopped like 4 times (for example on my way back from the shops i stopped my car in the driveway to see the smoke and it didnt smoke at all...its soo weird, suggestions? (turbo car)

My car has 220000 miles.
My car has an automatic transmission.