If she insisted you call the next day its a judgment call on your part, you could have but if you really wanted to set the tone early I would have waited just one more day then called. But if you really hit it off together and she seems like a sweet type then you might not want to jerk her around too much. Different types of girls respond to different treatment, one girl may get off on guys that are jerks and blow them off, others may not like that and forget about you. With experience you will learn what types of girls warrant what type of treatment. The bottom line is you are taking a risk whenever you cave in and start giving a girl too much attention too soon. That risk is her taking advantage of your niceness. But like I said, depending on what type of girl she is you might not want to start those little mind games yet. The problem with your situation is you are novice, so in order to safely undertake this whole dating thing, its probably best you do things like wait to call, make sure shes more into you than you are into her, etc. Its for your own confidence and protection.
Yes, make out with other girls, if anything you need experience with the actual physical act. Plus this current chick may flake out and you will be left with your dick in your hand. Just like that one time Im sure you remember.