Gdanning is correct, but I would also add that "psyched" and "pumped" are slang words often used by younger people as it originated from teen-speak. The millennials who I believed started using these words still use them as now-adults. "Thrilled" seems to be a word that younger people don't use, and seems normal to hear a baby-boomer say this. "Excited" is used by everyone. It seems to be a word that everyone accepts. :) But if I heard my 73 year-old mom say, "I'm pretty psyched about the farmer's market opening this weekend," it would just sound silly. But if my 28 year-old niece said, "I'm psyched about starting my new job," I wouldn't think anything of it. Along with psyched and pumped, "stoked" is another youth-favoured word that means the same thing. Some of these words were hi-jacked as slang from every day words in English. Stoked and pumped are examples of this. Stoking a fire causes it to blaze. Pumping air into a tire causes it to expand and become stronger. Psyched is a bit complicated. It comes from the word psychology, and used to be used as a way to tell someone "I fooled you". Example: "You thought the girl liked you but she likes your friend instead. You got psyched." It means that it was perceived that some psychology was played upon, fooling someone to think something else. But to be excited about something meaning "I'm psyched" could be a link to the word psychosis/psycho which means someone who has a violent mental disorder. Years ago, people used "mental" as a slang to mean that someone has lost their senses and reacts aggressively or emotionally. Example: "My mom went mental when she caught me smoking." These words playing on mental instability whether it's real or perceived became acceptable slang, to create a situation that sounds humourous. Most of the time, people who value the literal meaning of words and don't typically use exaggeration to communicate will not use slang like "psyched", "pumped", or "stoked".

They are very similar, although "psyched" and "pumped" are usually used to refer to upcoming events. "I am pumped for the football game tomorrow." A similar word to those is "stoked." "Excited" also is most often used to refer to upcoming events. "Thrilled" is more often used to describe ongoing and past events. "I am thrilled to given this award." "The roller coaster ride was thrilling [past]. I am excited/pumped/stoked to ride it again (future)"

Thrilled, psyched and pumped are basically the same and exited is on a little lower level of excitement.