Watson was particularly unhappy with her serve as she suffered her ninth first-round exit at Wimbledon.
“I was just so frustrated because I don’t think I’ve ever missed that many first serves and I didn’t feel bad,” she added.
“I was trying to change things up, trying to find the court, take a bit of pace off, but just nothing seemed to work.
“Every time I walked up to that line I was like ‘this is going to be the one, this is where it’s going to change’ and it just never did.
“I just think that sort of stress built up as the match went on; it was just frustrating that I couldn’t find it, especially because that’s the one shot I’m actually in control of.”