There is nothing wrong with upvoting your own posts btb (I'm calling you btb as it's easy)
excessive self-upvoting is when you also upvote many of your own comments and such, you can check you voting behavior on this website (this doesn't always show the true picture though).

It takes a while to find your own way of posting on this platform, a while ago I made a post on the steemit basics which might give some good ideas.

Feel free to ask when you have more questions !
I'm always open to help out if I find the time.