So I began taking progesterone supplements At 4 dpo. At 5 dpo I noticed that my breasts were swollen and I had gone up an entire cup size. I don't think that would be from 2 days of the progesterone supplements alone. Could my body's progesterone have spiked that high on it's own? Is that an early sign of pregnancy??? Even though I know implantation would not have occurred yet. Today is 10 dpo and test was bfn.