...it's nothing to be sorry about. In cartoon form, unless features are unrealistically exaggerated (large breasts, Barbi-esque curves, big red lips, huge eyelashes, etc) it is difficult to tell between male and female.

And I make no excuses for my still-developing skills at drawing women at the same level of detail as the rest of the characters in the strip. I could probably have drawn Sarah to look like Miranda or Pearl, but then she'd look like...Miranda or Pearl. :p

Please bear with me as I puzzle this out.