Completely normal man. I say that I struggle to even get mentally turned on after the rough workouts. If you're taking a preworkout supplement then understand that most will increase the amount of blood in your muscles, not your penis, as well as changing the pH of your blood to counter act a bit of the lactic acid burn.
I had a very similar issue and I asked myself this one question before I decided to take my concerns to google: "is my diet optimal?"
A nutritionisn't stated to me in a visit following my answer to this question, that I am lacking a fair amount of leafy greens and many macronutrients.
Testosterone is said to peak during a workout and hit a valley a certain period of time into a workout and never really recover without rest. I decided to not worry about anything I had previously noticed until I changed my diet appropriately. That included pumpkin seeds salads (great source of zinc- which is huge in hormone production), I completely rid myself of Trans fats and in their place implemented items such as broccoli, spinach and other nuts like pistachios. I changed my meal frequency to 5 instead of 3 a day and immediately noticed a difference.
I had more energy, and although I still had a bit of a lull in desire and ability closely following one of the hardest 2-3 hour leg day/cardio days, the lull would only present itself for a bit more than a half hour on average.
Of course this is assuming that you don't take a preworkout- if you do then you need to understand what stimulants often do to your body in relation to your our question.
For example caffiene has about a 4 hour half life and stimulates adenosine (an excitatory neurotransmitter- which also can constrict blood vessels if high enough quantities are present. 200+mg will cause a noticeable difference in your situation and even though it may be half Ed after your workout to 100mg since a fair amount of time may have passed, your bodys response to heavy lifting will be to send all the blood to the muscles.. if you are trying to move that blood to the penis and do so with small "highways" (constricted blood vessels) then you are already making it tough for your body of move it all are the once or even over a period of time.
Everyone is so worried about if there is something wrong with them- yet by doing so they're assuming that they are taking adequate care of their bodies.
If you ask me, optimize your intake before you judge your body's results to anything. And keep in mind that excessive protein is not a good energy source- but protein wasn't designed for that so it should be clear why that is the case. And if you choose to use carbs as your primary energy source (as your body actually intended) steer away from refined carbs and transfats because they will kill your testosterone production momentarily.
Increase fiber, b vitamins (b4 in accordance with zinc), drink dairy with vitamin d (if lactose intolerant then you should take a lactase supplement like I have you for your own comfort) whole grains are good. But I don't care what youre doing- unless you are ready injecting steroids, half your plate should be some shade of green and the other two quarters should be protein and complex/simple carbs.
If you do research beyond this post then I would suggest that you use academic journals that are peer reviewed because since the supplement market isn't subject to the fda testing the market is flooded with false super ingredients and stories bc the profits on these supplements are through the roof.
I hope this helps, if you have any concerns, do yourself a favor and respect your body enough to just ask a doctor or nutritionist instead of starting a game of Internet roulette regarding your health.
If you do decide to go with a testosterone booster as many males do with this issue I would advise you to look in to the supplement line by PhD Jim Stopanni because he uses only peer reviewed academic journals, actually lists every one of his ingredients and the dosages and has them third party tested for heavy metals and label accuracy- likely the only transparent supplement line out there annnnd he makes annnnd video explaining every ounce of ingredient he uses annnnd nd cites his sources so you can make your own educated decision.
Ito likely youre young and have no girlfriend or children and if that is the case don't worry so much about this issue- this is your body, and it's only considered wrong when you compare it to how you think it should be- don't stress over what you can't change- only fix what you can.
I can normally get an erection any time I please but it seems after I'm done at the gym till a few hours later its very hard I just want to know if this is normal or not...