You will be fine, as long as your not having it all day every day just every so often, than id say go and treat yourself!
They say up to 200mg of caffeine a day is ok. A small only has 75mg, youll be fine. You can also get any drink decaf or half caf.
I am 38+2 and I have about one cup of coffee a day
Once in a while don't hurt :)