Meaning Of My Dream

Most of our dreams are weired and have no clues. We usually see things in dreams about which we are thinking the most. Your all dream is focused on your pregnancy and your strong wish is to have a baby.

I am giving you three websites from where you can have the expert opinion of your dream.
Dream Meaning
Dream Meaning
Wikipedia

A dream is the experience of envisioned images, sounds, or other sensations during sleep. It occurs in humans, most mammals, and some birds. ...

Some of our dreams have no meaning at all; they are simply a way for our brains to process through all the subconscious thoughts and experiences we did not process while awake.   Sometimes those unconscious thoughts be translated through our semi-conscious sleeping minds in some pretty bizarre ways.   That's why sometimes the strangest things can be mixed together!

It sounds like you may have had that sort of dream this time.  Since you are trying to conceive, understandably the dream centered around the pregnancy theme. The cream instead of milk mistake suggests a translation into real life that one really does not know for sure if one has conceived...  That always wondering "am I really pregnant yet?" feeling that goes along with trying to become pregnant, and hoping one is.

By the way, other kinds of dreams are said to contain symbolism of some sort, but not all dreams do.  Jungian psychology (after the famous psychologist, Dr. Karl Jung),suggests that in symbolistic dreams, each character in the dream represents an aspect of ourselves and the collective unconscious - (through archetypes).  Jungian dream interpretation takes years od study in psychology, but for a basic overview and some interesting tips, and maybe some insight into other dreams you have had, you can go to this site: Jungian dream interpretation

Good luck, with both the conception and with studying (and realizing!)  your very best dreams :)