But what you have to realise is that a 10 minute walk is exercise, 20 minutes yoga is exercise, a 15 minute run is exercise. Not every workout has to be 60+ minutes, or you have to be dripping in sweat and exhausted afterwards. Infact if you are super exhausted after every workout and you have no energy for anything else then you should reevaluate why you exercise. When i over exercised i had absaloutly no energy for anything else in my life. I cancelled plans because i had no energy and didnt want to leave the house because i was so exhausted after my workout.... i was doing too much. Exercise should GIVE you energy.
Now when i workout, i can get up at 5am and workout before school and i love it, i have lots of energy the rest of the day and i still have energy during the evenings. Now my workouts are alot shorter than before, usually 45-60 minutes which includes warm up and such. And then if i do HIIT after my workout then the whole workout is still not more than 70 minutes long. I dont sweat after every workout, some workouts i need to lower my weights, other times i can do supersets and other times i need 2 minutes rest between each set... it all depends, that doesnt make one workout not effective or not exercise.
You need to remind yourself that exercise should be FUN. It should give you energy, give you something positive. Not wear you out and tire you out so much that you dont live life. Then you need a break from exercise to let your body recover and rest. Unless you are preparing for a competition or some elite athlete you DONT need to do several hours of exercise a day, you dont need to push yourself to your limits each day... that isnt healthy. Even elite athletes have recovery workouts and take it slower, pushing yourself too far everyday just leads to bad consequences. Infact elite athletes can suffer from burn out and over exercise and injuries quite alot during their careers because they push themselves so far for competitions and such, there are many athletes who by the age of 30 or so have serious injuries stopping them from doing their sport.....
If you are just an average person (sorry, lack of better word), someone who isnt an elite athlete and is training for the Olympics or some other competition, then having daily activity and some exercise form you enjoy is all you need to stay healthy. You're not going to get any results, mental or physical by pushing yourself too much, that can lead to burn outs or other consequences.
But back to the main topic.... feeling like your workout isnt good enough. Well you need to remind yourself that all exercise is exercise. If you struggle with these thoughts then i suggest that you PURPOSELY shorten your workouts, you do less, you feel and cope with the anxiety you get. I know it might feel like a storm inside your head because you are doing less than you had planned or want to, but its the only way to overcome those thoughts and to learn to exercise for the right reason.
Another tip is to workout with someone else.... then you cant just do what you want and keep going for eever and ever, instead you take it more calm and have some social time as well as exercise time.
And also a note... You dont have to sweat every workout and you dont have to feel sore after every workout for it to be effective!!