Advice needed please.

Don't know if this is the best place to ask for advice.. But I gave birth 4 weeks ago and since then I only go to the toilet once a week for a number 2 which isn't normal for me and when I go it's extremely painful and every time I wipe afterwards there is a good bit of blood.. Sorry for tmi but does anyone know what the reason for this could be ? I thought it could have been piles so I've been using a cream for a week and a half but that hasnt helped..