6 month old bleeding from butt

Hi folks! Typing this and feeling extremely sad and helpless. My LO is 6 months and we just started solids last Monday. He has not pooped since i have tried prune juice, apple juice, fennel tea, now doing suppositories and laxatives. Today i changed his diaper and there was blood in it. The doctor said to increase laxative. Please tell me if anyone has a similar experience. I am a FTM and i am worried about what is happening to my baby.