Hello darlings. I've been on Estreva 1.5 - 2 mg and spironolactone 50 mg therapy for 4 months, and I experience pain during erections, which are incomplete. Is this normal? Will it go away with time, or will I always have this problem? The sensation is like if it is not supporting the growing, when it shrink the pain stops. I use estradiol gel on my inner thighs, up to my groin, before bed and I get an erection while naked. Could my testicles and penis be receiving too high a dose of estradiol overnight, causing some kind of internal problem?

Yes this is quite normal. The tissues will athropy mostly from lack of practice and the blood pressure builds up in a way which could hurt as your body is trying to get the usual amount of blood down there beforeit adapts, the body changes tend to ba faster than what your brain can process, so confusing weird stuff and things not working as before is to be expected. 

Unlikely that it is anything other than athropy pain from HRT.