trust me m8 there is no mistaking gyno!, it just doesnt suddenly creep up on you and bang you got gyno, the puffyness you have will be water acumulation in the skin!, it shows up more on the nipple because you nipples are made of realy thin skin.
i can tell you how it feels because ive had it and it was painfull!, first thing stop playing with your tits because you will get some funny looks, also you will make them tender and this can be mistaken for gyno by yourself.
When you start getting the first signs of gyno your nipples will be very sensitive and tighten up and become erect quite alot, (but this can happen to most guys and they never get gyno), then a few days later you will feel a pain behind the centre of the nipple or just above centre and it will feel like you have got a very sore boil behind the nipple, no lump but a feeling of soreness, then a few days and you will notice a small lump the size of half a garden pea maybe a little smaller behind the nipple, then from then on the lump will get bigger and bigger feeling like you have a large marble behind your nipples, by the time you hormone levels return to normal and the lump stops growing, then the lump will regress slightly and then you have a brand new pair of tits for the lads to stare at if there in to that kind of thing
if you havent got any of those symptoms dont bother with the nolva!, i am a firm believer in only using a compound when nescersary!, and if you use nolva now when you dont need it!.. you have to use it for all your cycles because you truly dont know wether you need it or not.
but seriously if you get gyno you are the first one to notice it! not your friends, because you will have pain and a lump growing under the skin!, it will be kind of disc shaped.. round and flat, mine was to the size of a 1pence piece and about 8mm thick before it started showing!, so your friends just noticing your water retention thats all.
Unfortunatly for nolva doesnt work and only makes gyno worse for me!, and over the years the gyno got worse and had to get it cut out, but this only happens in an extreamly few people.