anxiety when standing/walking?

[Avia Juliet]

For the past month and a half my anxiety has been pretty bad.. due to some issues that I'm really trying to work on. Lately, the anxiety seems to be getting better but gets worse when I stand up or walk long distances. For example, I was just dying easter eggs (yes, I'm 18 and I still dye Easter eggs lol) and it probably took about an hour. At first I was okay but within the last 15-20 minutes I started to feel very tired, out of breath, nervous stomach, and just started to feel anxious. I sat down and within 5 minutes I felt completely fine. My anxiety has mostly been social anxiety.. for as long as I can remember. But within the past few months the social anxiety has gotten better and this general anxiety has kind of come out of no where. Prior to this the only time I would feel this anxious was before a doctor or dentist appointment. For the past several years when I would have some kind of appointment I would feel very anxious beforehand and was okay if I was sitting, but when I stood up I instantly felt like I was out of breath, had NO energy, and was very anxious in my stomach. This feels like that. But I wasn't anxious to begin with so it doesn't really make sense. I'm starting to worry that this could be something else..

Also, I'm not currently in therapy or on any medications. I would like to try therapy, but I'm scared to talk to my parents about this because I know that my mom (and possibly the doctor) will try to get me to take medication. Which I'm not totally against, but I would prefer not to take it if I can avoid it. Though I am starting to worry that this is not anxiety. I've been eating a lot less lately because I've been kind of stressed and just busy. Do you think this could be caused by under eating? Any help would be appreciated..