If you are an INTP, you are BY FAR the most perceptive INTP I've ever seen. There is a lot you pick up on that an INTP would completely miss and not even care about. You're also too feely for an INTP, imho. I think that side of you, while repressed, operates actively internally. I'm picking up on strong Sp 4 influences in the way you make light of heavy situations and I get the sense that there is much more to you than meets the eye. What I'm trying to say is that you don't match the image of INTP + 5 + Sp-first. I would expect much more detachment and not be able to pick up on what I'm sensing within you (which of course could be wrong, but I'd be surprised). I'm not calling you soft or sensitive, per say, but I don't think you're as detached as you seem.
For you, I think perception > judging, same with me. Ne doms often confuse themselves for introverts because intuition is such a private, internal process and yes, they do tire from too much time spent engaging (perhaps the senses fatigue).
I like ENxP Sp/Sx for you with heavy 4 and 5 influence. Now, there is a slight problem with this: You have high Ti and Fi, which are the PoLR functions for the opposite type, so an ENTP wouldn't have high Fi, and an ENFP wouldn't have high Ti. I tested high on Ti for ages because I misunderstood the function. I'm pretty concerned with knowledge and competency and am stubborn with what beliefs I subscribe to, even intellectually, but that's not Ti, that's just my 5 influencing me to want to be knowledgeable and competent. If I truly assess myself in an objective manner, I realize that I can easily believe in something and then a week later change my mind (from a logical perspective, like say the process of self-typing based on observable data). I can hop all over the place with how I categorize things I observe or reflect on, and most of my knowledge is actually about things I find useful to me or researched on a whim as opposed to expanding on an internal framework.
I probably explained that super shittily, but the point is that I think it's more likely you are a withdrawn cognitive extrovert. I basically test as a straight up NFP riding a line of introversion/extroversion, and I think you are similar and that comes from the Enneagram type and dominant instinct.
Alternately, assessing your use of Si could lead you to a final answer. Mine is notoriously weak, to the point where my ISFJ coworker basically has to be my mommy and make sure I don't forget about certain things and get things done. I use Si in some of my daily habits, but I loathe planning everything and sticking to a total routine, and closed-mindedness or old fashioned thinking are my top triggers, so to speak (inferior functioning). I don't really fall into Si tertiary temptation like an INFP would, who might enjoy watching a favorite movie over and over again. I would much rather explore opportunities for bettering my life by finding useful information, products, or making my home more comfortable with random creative decorating (I love moving my furniture seasonally to improve the flow of things). More often than not, I am lazy and seek novelty and knowledge online in a somewhat neurotic and impatient manner, which can feel introverted but really isn't when you think about it.
Too much rambling, be gone, Pete.
*throws smoke bomb at ground but malfunctions and has to retreat in shame with stiff nervous smile on face*