I got my first full time job at the start of the year as a software developer. Previously I had been working casual at about 6 hours a day 5 days a week also in software development. Almost all of the issues I was facing moving up to a more serious software development job I have overcome but the one thing I just can't overcome is I just can't work an 8 hour day. Every day I get to about 30 minutes to 2 hours from the end of the day and I just feel so tired I can't get any work done. I spend an hour stuck on something and then get it done in 5 minutes the next morning.
The manager has noticed this and regularly reminds me to try to stay focused in the afternoon and put in more effort. The problem is I am already putting in my full effort. I'm not playing on my phone or reading reddit, I just can't get anything done in the last hour of the day.
Is this a normal thing to experience? Is there anything I can do about it?