Altitude sickness is read as climbing too high too fast. Tradition links it to ambition or success that leaves you short of breath, and to the need to acclimatise before going further.
Has this come up in your dreams before? What was going on in your life then?
My Cosmic Code has a private dream journal. Write a dream down and the app picks out the symbols in it, shows what dream books say about them and, over time, which words recur across your entries. The journal is stored on your device only.