u/Lazy-Watch7569

Does this look like blood to you? The streaks are more brown than red. She had no occult blood 3 weeks ago. Started Alimentum RTF 2 weeks ago. I really don’t want to change formulas

My newborn was having seemingly seedy poops but the watery part was significant and because it was soaking the diaper, doctors couldn’t see the wateriness and weren’t suspecting any allergy or intolerance. However, the frequency of these poops was uncountable. She always had a poopy diaper. She wasn’t gaining weight, not even enough to reach her birth weight. But she wasn’t dehydrated or sickly either. Doctors mishandled our case and fortified her Similac 360 formula causing more diarrhea.
When she turned 3 weeks old, I decided to switch off fortification but kept her on Similac 360. We saw weight creep up very slowly but stools were still bad. It was one step forward and two back with the weight.
At 4 weeks (first picture) noticed sudden increase in stringiness in her poop and severe acne and persistent poor weight gain. I decided to start Alimentum RTF. Saw sudden weight gain, clearing skin, poops are frequent but not as bad as before and more pasty instead of loose but they have some mucus in it (second picture)
Do you think that improvement of symptoms means that she has CMPA? She never had blood in her poop before, not even microscopic. But recent (second picture) diaper or two is showing this amber colored mucusy strings? Is that blood? Could it be possible for her to have blood now after being on Alimentum for a week and a half? Would it be something residual?