In all honesty, I must say that when I read the title of this thread I…ah…thought you meant something rather different from ejaculatory prayer

I thought you might have had some issue down low to be frank!
I would personally use the word “exultation” or “ecstasy”/“ecstatic experience” as opposed to ‘ejaculation’ so that people don’t get the wrong impression

Its not you Robert, your 100% accurate in your choice of words, however most people think of semen when the word “ejaculation” comes up rather than spontaneous outbursts of joyous praise for God.
On the actual question of a joyous exultation type experience, yes I do have such experiences from time-to-time, although not so frequently as your good self brother Robert. I am actually glad that I do not have such feelings on a frequent basis, because it is not good to rely on anything other than God, nor to be attached to anything other than God. While these consoling sensations of spiritual joy are indeed pleasurable - I usually get a feeling in my chest that kind of ‘catches’ my breath with a pleasing sense of heat, sweetness and serenity - we should never come to rely upon them or become attached to them, for they can distract us from continual remembrance of God above all things. The height of contemplation is not experienced through the five senses but rather when the senses have become still and we experience God in a kind of nothingness at the heart of our being, as the Holy Spirit from within touches our spirit and we are lifted out of ourself completely, feeling nothing, “robbed of all sensation proved” to use the words of Saint John of the Cross.
What I do find particularly commendable in your practice is this part:
I don’t really say prayers, but I think of God often and I listen for Him in my heart
This lack of vocal prayer, and even of thoughts, this intent “listening” into the silence of our hearts for God’s voice and presence, is the gateway to the gift of contemplation. It is a form of prayer, the highest, listening to God rather than trying to “converse” in a human way. It is the kind of wordless, thoughtless, interior receptivity which is a prerequisite for contemplative prayer - which of course can only be initiated by God through grace and not our human effort.
Contemplation is a divine gift which is given to the one who wants to share silence with God in a state of still detachment from sense perceptions, content to commune with him in “spirit and truth” without attachment or dependancy on the senses, on words, thoughts, desires - on anything apart from resting in the Presence of the Lord.