When it comes to vocations we all have a choice. God may be calling you to be a priest or maybe He’s not. If you’re not ready and the idea of priesthood is causing you distress then you certainly shouldn’t try to force yourself into it. Even if God is calling you to the priesthood you don’t have to say yes. God won’t be angry or punish you even if you reject his “plan A”. That said his “plan A” will bring you the most peace in the long run.
In matters of discernment the best advice is to work on your primary vocation. Our primary vocation is to holiness, loving God and neighbor. If you focus on that you will find peace in whatever state of life you’re in and everything else will flow from there. You’ll also find it easier to hear the voice of God over the voice of the world, the enemy and your own voice. When you follow the voice of God fear will fall away and you’ll find peace in whatever he ask you to do.