The 19-year-old centre-back was selected by Rafa Benítez for the Magpies' final Premier League game of the season - and was an unused substitute in an emphatic 4-0 victory at Fulham.
The following day, Watts featured on the losing side for the under-23 squad after a 2-1 defeat against Southampton in the Premier League 2 division two play-off final at St. Mary's Stadium, inflicting a second final defeat after a narrow 1-0 loss to Everton in the Premier League Cup.
Watts told nufc.co.uk: “I think in football it sums up what you can go through. I went from the lowest emotions to the highest in the space of a week. Obviously, that is what football can do to you and it's a bit of a learning curve.
"To be the bench and having that experience with the first team squad was amazing. The next day I lost a play-off final, going from one of the highest points to the lowest. A lot of players experience that so I think, going forward in my career, I can use that to help myself and be able to benefit from it.
"It was a very proud moment. It's something that, when you join the club at eight, you think are so far away from at that age. You keep going through the academy ranks and then to be told by Ben (Dawson) that I'd be travelling to Fulham, you think this is what you've done everything for. Everyone wants you to do so well and to hear the news was great for myself and my family.
"It's a team I've supported since I was a young lad and one all my family supports. It's where I live and have been brought up my whole life and to do it for my boyhood club means that extra ten percent compared to being on the bench for another team.
"When you're on the bench in any team, it's about being ready. You never know what the manager is thinking and when a couple of defenders went down looking injured, I made sure I was ready, warming up on the sidelines. I was delighted to be on the bench so I was ready at all times if I was called upon. That wasn't the case but I was still absolutely delighted to be there and travel with the squad."
Watts, an ever-present for the under-23s, looked back positively on a first full season with his boyhood club after signing a professional contract with the club last summer.
And, despite missing out on a cup and promotion double in two successive matches, the Academy graduate is hopeful of another impressive season with United's second string whilst admitting his desire of breaking into the club's first-team.
Watts added: "I think the team has been successful despite the two final defeats. We still had to get there and we done everything right to get there. We were unlucky not to win one because I felt we deserved at least one due to the team's professionalism and the hunger to win games. We have tried to play the best football we can which has been brilliant. It's a young team with lots of potentials. We keep learning and strive to get better.
"Being on the bench in the first-team gives you a little taste. Because of having that, I want more and, to get more, I know I need to work harder and make sure I listen and learn more to people ahead of me as that's the only way I can get there."
"It's my first full year as a professional and I've really enjoyed it. The level is much higher and we've played more than 40 games this season compared to under-18 level where I was injured for the most part of it and we didn't play as many games. I've also played in a new position as a centre-back and this season I've been learning under Ben and the more older players in the team."
