my tires are 4psi under the recommended limit, am i still ok?

You should be fine. Just keep an eye on the level. You will however lose some gas mileage and wear your tires out faster. But with only 4psi under, you're not gonna have much of a problem at all. If the car starts acting funny; like swerving back and forth, or the steering feels different, go ahead and fill up the tires. I know it's cold out, and you don't want to get out of the car. Understandable. But first warm day, find a gas station with a free air pump and fill up the 4psi. But if you're like me and too lazy, you will be fine. =D

It's not ideal but you can still drive. Running with the tyres under the correct pressure causes the outside edges to wear quickly, and increases fuel consumption due to the extra drag that it creates. Pump them up when you next have the opportunity.

Only if you like to wear your tires out prematurely and adversely effect your vehicles handling, stopping and load carrying ability.

Sure you can drive it. Buts its costing you gas mileage. .............&&&