A related discussion,
mature growth - post 40 male was started.
Further to my last comment, yes, I did take account of time of day etc. when being measured, before anyone asks. I perhaps should also have mentioned that my whole family seem to have experienced various symptoms of sex hormone imbalance at one time or another, which might be relevant as I gather it is oestrogen that closes bone ends at the end of puberty and so stops further growth (Is this the mechanism that causes women to be on average shorter than men? That is, they have more oestrogen, so their bones close sooner?). Perhaps a disruption to the process left my bones 'unclosed' and so able to add a little extra at a later date.
I'm 30 and I've just had a very late mini growth spurt. Some time in the last two years I've grown half an inch. This sounds a bit freakish, but I would never have noticed if I hadn't started checking my height again occasionally after my kid sister had a late growth spurt (at the age of 21), so I wonder if it might actually be a common occurrence - how many adults actually check their heights, after all? Incidentally, I need my extra half inch - it means I am no longer lying when I say I'm 5'4".
I know from personal experience that you can have late growth spurts. I was 6'1" when I graduated from highschool (aged 17) now I'm 6'4". I didn't stop growing till I was 19 or 20. I'm 27 now so I've got nowhere to go but down :)
The most important thing to know is that height doesn't matter. You may shoot up an inch or two before you stop growing, or you may not. The important thing is to learn to be happy with who you are and how you are. You will no doubt have strenghts in other areas. Focus on what you are good at and the advantages to the height you are now.
I don't know if late growth spurts are hereditery but I know it is possible for you. My husband was about 5'6" or 5'7" and went through a major growth spurt right after he graduated high school. People who knew him from school and see him now can't believe it's him. Anyway it does happen occasionally, my husband is now 6'2" tall. Don't worry about how tall you are.