Floaters could erupt from anxiety, stressful time in life, aging and even for no obvious reason. if it is your only symptom most probably it wouldn't be considered to be hppd, but that shouldn't matter for you. i also have those floaters, i started noticing them months after every other possible hppd sympton was already in sight and i would say they didn't change since they just came up one day. now it is by far the most irritating and noticeable symptom.
some people all around the web (other hppd forums and drugs-forum.com) just do not concider floaters as an hppd sympton because it's a natural phenomenon that apears in many occasions with no relevance to drug use. this is true, but then again its also true for 'visual snow' and afterimages.
if you would ask me, it does have a clear connection to hppd since my own experience and many others in this forum report an increase of floaters. with that said, i can also recall seeing floters since very young age upon bright skies, but not a near intensity as they apear today.
Seeing an ophthalmologist is probably the best advice, but you should know theres very little you could do about it exept giving it time, they probably subside if you are distracted and not concentrating on them too often, otherwise you will get use to them, anyway you will be fine!
I could share with you another two experiences of two folks i was discussing with on that matter:
one of them haven't done any drugs and he had floaters since seven years ago (29y old today) and the other did done all kind of drugs and he has floaters for about the same time. the second one claims he doesn't think the floaters have anything to do with drugs, but they both report that they aren't noticable anymore, they need to look for them in illuminated rooms to see them.