Suarez joined Arsenal in January but made only six substitute appearances under Unai Emery, four in the Premier League and two in the Europa League.
The 25-year-old played no part in the team's run-in, with his last game coming against Manchester United on March 10, when he was introduced as a late substitute.
"On the 16th day of arriving at Arsenal I was not even 50 percent (fit), it was a year to forget but also to learn," Suarez told Spanish radio station Cadena Ser on Thursday.
"I thought I had torn my groin and they did a scan and saw that I had an oedema (an excess of fluid) around the bone in my pelvis.
"I was in a lot of pain and from then on I carried on training with medication and put up with it as best I could but I didn't feel right and Emery didn't think I was right. I wasn't comfortable.
"I don't think I was even at 50 percent fitness. After 15 days of being at Arsenal, I wasn't right."
Suarez has struggled for games under Ernesto Valverde at Barcelona and says he wants a move, preferably to a club in La Liga.
"At Barcelona I think I'm not going to have the opportunity to play regularly and what I want is to leave and to play," Suarez said.
"I don't know where, wherever is best for me. I have to look at everything. My idea is to stay in the Spanish League, to be near home and compete in La Liga."