I used to breastfeed my baby on the left breast most of the time especially at night and now I sometimes have a weird feeling on the same breast like pain from a distance. Could there be a problem?

Firstly it is important to feed you baby from both breasts.  The pain could be caused by a blocked duct. You can do a breast exam and see if you feel any lump on that breast. If you do, you can massage the breast, moving your finger towards the nipple to unblock the clogged duct and that should ease the discomfort. If the pain persists however, please see a lactation support consultant or your doctor for further investigation.