I think if you're feeling something is missing in your life, maybe take some time to examine where you're at now and figure out what it is that's missing - maybe more babies, maybe something else.
As for age gaps - there's no right or wrong and I think everyone just tends to make the most of whatever they get. You have plenty of time before next Feb to talk this through with your DF in any case.
:yeahthat: wonderfully said Marcellus, i agree give yourself some time as these are still early days and i can still remember with a newborn my feelings seeming a bit confusing and little all over the place, lots to take in at these early stages and yes lots to consider and think about that you never did before you precious DD arrived, it can be the responsibility of being a parent that you are thinking of her future and your's that comes into it all these emotions of what to do or not to do, there is lots of time to talk with your DP until Feb !! ... And if your considering a career in the workforce outside of Motherhood (which is a massive job already) that will need to be taken into consideration unless you are already working/studying (??)

... and as far as your being young please take it from old lady me lol put that all aside, your a Mum now whether your in your 20's or 40's do what feels right from here on for you and your little family and forget about the number of age you are