Flesh/pink/brown colored flat bumps on arm

Hi, I posted this a few months ago and have been unable to figure it out. I have had a series of small, fleshy/pink/brown patches on my arm since October. There are three in a cluster on my forearm. They do not itch at all and have not grown in size. Sometimes they appear to lighten or fade if it is slightly warmer out (it's been freezing lately). They  are not abnormally shaped and are sometimes dry. There is then a few small slight rash-like patches up my arm, they fade quickly and often do not come back unless, again, it is cold. I saw a dermatologist in late November/ early December who determined it was Prurigo Nodularis and related to my high levels of stress because he saw similar spots on my legs. It made me wonder if I had been rubbed the spots in my sleep or something? He gave me a stronger prescription cortisone cream which helped some but I ran out of the cream and was not able to get more. I am considering going back for a follow-up. I also have a pretty shaky diet, I'm a vegetarian and don't drink enough water. I've been trying to improve my diet and drink more water but am not sure what that does. I also wear sunblock in the summer months and have been wearing long-sleeves all autumn and winter. At first I thought it was a reaction to the material of the clothes I've been wearing lately because as a child, I had a slight reaction to polyester but nothing this odd. Does anyone know what this is? Thanks!

[Fr4nk3l]

A few more things should be noted:
1. I was studying for the GREs and have been concurrently looking for a new job, applying to schools, and dealing with personal things which have increased my stress levels
2. I am in a monogamous relationship (we use protection all the time). I thought it might be the result of using his towel at times because it isn't always clean and is sometimes damp when I use it.

[maatson]

Prurigo nodularis is an extremely itchy condition, and from your description, your lesions do not itch. I would rather think of a lichen nitidus, or verruca. If you could let me have a look at the pic, guess could give you a better idea.
Regards.

[maatson]

Granuloma annulare,  in the form of discrete papules, from the photo.