Does sound like a blocked duct, I always found blocked ducts on the underside more tricky to unblock with massage, just more awkward and 'like a bruise' is exactly how mine felt.
Do watch for Mastitis symptoms though, I've had it and it's horrible, but as soon as I was given antibiotics the symptoms dissapeared. Found the following on nhs24 website;
The symptoms can include:
High temperature; Redness, swelling, and hardening in the affected breast; Severe breast pain when pressed (tenderness); Enlarged and tender lymph nodes in the armpit; General aches and pains, and headache.
You may also be aware of a cracked nipple or a break in the skin. If you are breastfeeding or expressing milk (using a breast pump), you may notice that your breast is very full (engorged), because it is not draining properly. Women who are breastfeeding might also find that their baby does not want to feed from the affected breast, because the taste of the milk has changed.
I was also vomitting and shivering.
Hope the hot bath and massage does the trick, another thing I found helped was hand expessing whilst massaging just to try and get the milk flowing. Think the tight bra probably caused the problem. The joys of breastfeeding!