When you are very excited or nervous about something, you might use the phrase "more keyed up" to explain your state of mind. However, there are many synonyms that convey similar meanings. For example, you might say that you are feeling "amped up," "jittery," or "on edge."
If you are feeling excited specifically because of positive anticipation, you might say that you are "thrilled" or "eager." Alternatively, if you are nervous or anxious about something, you might use phrases like "frazzled," "panicked," or "unsettled."
Ultimately, the choice of synonym will depend upon the context and the speaker's personal preferences. Regardless of which expression is used, it is clear that the person is experiencing an intense emotional state.