The 14-year-old stormed to silver in the women's 200m butterfly in Utrecht, smashing her personal best with a superb time of 2:17.24minutes.
And, while that was not good enough to grab gold, which went to Spain's Carmen Balbuena Heredia, Stephens was grinning from ear to ear after collecting her first medal of the Festival.
"In the heats this morning I swam a new personal best to make the final but I then smashed that by almost two seconds, which is amazing," she said.
"It felt amazing to be up there on the podium collecting my medal, I am very proud and the atmosphere in there was amazing.
"There was so much support for Team GB, it almost felt like a home away from home, and the pool is very fast so it was a lot of fun.
"I went out a bit too hard in the heats and that cost me at the back end so in the final I took my time a little bit and that proved to be really good.
"I pushed in the second and third lengths and then held on at the end so to get the silver and personal best is just fantastic."
But Stephens is not done there, she will have a day off before returning to the pool later in the week for the 100m butterfly and 50m freestyle events.
And Stephens is adamant that there is still more to come from her in the Netherlands.
"The 200m is not my best event, I think the 100m event is so I am hoping and am confident that I can do well in that as well," she added.
"To be swimming the 50m freestyle feels great to be honest, it's a bit of a bonus and I did not expect that I would be swimming it at all.
"But the 200m result definitely surprised me and exceeded my expectations so I want to carry on from that.
"The Festival has been great so far, the noise in the pool is just amazing and I am loving the experience so much.
"Now I have got a medal I am looking forward to enjoying the rest of the week."