is this septoria?

[winstonl]

hello, this is my first post. I am a relative newbie to tomato growing. last year I grew in a greenhouse, I wasn't careful about humidity, and I had a lot of septoria early. this year I am a lot more careful about humidity and splashing water on leaves. I am noticing this on my brandywine. does this look like septoria to you? it was on the lower leaves. the only thing that makes me think that it may not be septoria is that it tends to be on the side of the plant that is exposed more to the fan and also the heater (at night). maybe it is due to plant stress? thanks for your help tomato experts!