For the past year or two, I have noticed some strange things with my penis both flaccid and erect.

Erect: I noticed that sometimes when I'm hard the skin on the back-top part of my shaft, just under the head, can get like tender and lose sensitivity. I don't masterbate a whole lot so I'm confused why this occurs sometimes. Also, after ejaculation, sometimes my penis will basically shrivel up, get like much skinnier than it is normally is flaccid, and the head of the penis stays somewhat larger than the rest of the penis. It also feels far less sensitive in this state. I know your penis getting smaller after ejaculation is normal lol, but what I described above is something that feels different and is new to me as of 1-2 years ago.

Flaccid: This also may seem normal, but I've noticed that my flaccid penis tends to vary in size a ridiculous amount. Erect I'm 6", but flaccid I can vary from 1.5"-4". When it's closer to 1.5" the penis becomes like very "tough" if you will and doesn't feel as sensitive. The skin at that size is like bunched up with lines in the skin from like fat roll line marks. I want to avoid being closer to that 1.5" size. Do I lose weight? Should I try creams?

It should be noted I had testicular torsion surgery about two years ago when I was 23. This is when I started noticing the penile issues, but maybe I was just more focused down there because of the surgery. I am 25 years old, 6ft, and hovering around 160lbs. Going into surgery I was about 140lbs so I've gained a decent amount of weight since.