How long should you wait before xontacting someone you just met?

If I just met someone new and got their numbers, how long should you wait before contacting them?

I am a college student. I met 2 people (one guy and one girl) at a social event. We talked for about 30-40 mins and had a great conversation and then exchanged numbers.

The thing is I met them 3 days ago(on Wednesday). I am planning to contact them today (on Saturday) but I feel like i waited too long.

Did I wait too long to contact them?