I am 50 and have had floaters now for at least 7 years. It started with one big one in the center of my left eye vision, since then, they have now appeared in my right eye, as well, like coiled up hairs/particles of dust and squiggly lines..like clear molecules, of different shapes and sizes....they also appear in my side vision, upper and lower, all around. I, too, spend too much time concentrating on them and it scares me! Also, I do believe that there is a direct corellation between allergies and floaters with increased blurred eye vision as well. It seems the worse my allergies, the more I notice my floaters and/or more dense. With proper/restful sleep, too, they become lessened. So there are many factors, I think, from allergies, to a disruptive nights sleep which will make them worse. And, yes, my vision gets more blurred when both occasions arise, allergies and lack of rest/sleep.
The floaters move around on the back of the eye. Unless you are having flashes, loss ofperipheral vision or showers of new floaters the movement you described can be considered normal
JCH III MD