At what point (or ever) is it ok to date multiple people?

I was recently single and new the the dating scene and, for the first time, made a Tinder account.

Early on I met up with 2 different people and over the course of a couple of weeks had 2 dates with each. At the time I thought it was usual – these were not actual relationships, we were just getting to know each other. Eventually I stopped seeing one girl and the other has now become my GF.

However, I have started to feel very guilty about dating 2 girls at once. Nothing happened with either during the time we were dating – certainly we never committed to being in a relationship.

I feel a bit weird about it all now. Is it usual to date multiple people early on before deciding to actually start a relationship with someone?