The American former world number one, who retired in 2006, said his first steps into coaching were "challenging, interesting and educational".
"When I played I never felt pressure but a lot of stress. As a coach I never felt stress but a lot of pressure so that was an interesting difference," Agassi told Britain's The Telegraph newspaper.
"As a coach you have to make sure you're saying the right thing at the right time or not saying the wrong thing at the wrong time - there was a lot of pressure to it."
The 48-year-old did not rule out working with Djokovic again despite the Serb reuniting with his long-time coach Marian Vajda.
"If there are ways that I could help him (Novak Djokovic), he'd have to let me know," Agassi added.
Agassi, a Wimbledon champion in 1992, expressed his willingness to coach anyone who needed it but was unsure about Australian maverick Nick Kyrgios.
"Would I help someone if I could help someone? Of course I would," Agassi said.
"What I think of him (Kyrgios) and his ability and upsides are different to saying you could work with him. You don't know if somebody wants to be worked with."
(Reporting By Arnab Paul in Bengaluru)
