Dear Pat,
Before getting to your question, let me tell you how great it is to see that your discernment is truly active and not just a vague entertainment of some feelings or an idea in your mind. You have been actively letting go of what needs to be let go of, and you have been defending your vocation when others don't understand. I think you have broken a major barrier that everyone who is considering a vocation faces. Congratulations. God has been active with his grace, but he always is; and you have been active with your correspondence, which we aren't always.
Now, as regards your question. Priesthood right now seems more like a cross you are taking up out of obedience than a joy. The notion of spreading the gospel does make you want to get up and go, but not the other aspects of a priests ministry.
Pat, I don't think there is anything necessarily wrong, as long as you don't stop here. It is actually good that you are experiencing a little of the cross, it shows you at least that your motives in following your vocation are neither shallow nor selfish. But it also shows that there is still a way to go in your relationship with Christ, deepening in the faith you already have, enriching it with hope and maturing it in love.
However, I would advise you not to put the cart before the horse. Don't be focused on feeling joy. Some joy is superficial, and it comes from superficial things like the company I'm in, an activity I enjoy, a novelty I experience; this joy is as fleeting as the causes that provoke it. But there is a deeper joy, the peace and serenity that we can experience even in adversity and persecution that comes from the satisfaction of knowing we are being sincere authentic, faithful despite the circumstances. It doesn't depend on external circumstances; it has its source deep in us, the life we live, a conscience that is at peace.
So, focus on getting to know Christ more, developing a more personal relationship with him, imitating him, seeing your vocation as a following of him rather than looking at the burden it entails, even when the burden makes itself felt more.
True joy, a different, fuller, surer, more lasting joy will be your reward.
God bless.