To me morning sickness is very comparable to something like the flu...or car sickness... I feel very nauseous prior to puking. If you were crying to the point of hyperventilating then I would guess it more to do with that. The fact that your late for your period tho is grounds for taking a pregnancy test to rule out pregnancy. If you are under stress lately that can affect ovulation which can delay your period. First step to confirm or rule out is to test.