Given his allergy to dairy and the fact that soy formula has been found to be very unhealthy, PLEASE don't stop breastfeeding. This really is a temporary problem. Just get him back on the breast. For the biting down, I learned to be ready and just stick my finger in even before the "clamp down" and unlatch them. For my boys, this would happen when they were just about to fall asleep. As far as increasing your milk supply, nursing more frequently is best and given his recent cold, it is SO very important to give him the fantastic immunity that is provided by breastfeeding. Breastmilk or formula MUST be a babies primary food for their first year for optimal nutrition. I don't want to lay guilt on you as we mothers get too much of that already, BUT of all the choices I've made for my sons in the past 16 years, I know that breastfeeding was the one decision that I have no doubt was right - all the others sometimes leave me wondering, like if I did the right thing sending them to a tough private school, being a strict mom on some things and a hippy mom about others, etc. So, please do contact La Leche League - there are local groups everywhere and the leaders are trained to coach you through these problems.
Also, that emotional connection is equally as valuable as the nutritional one for breastfeeding. Both my teenage sons remain close to me and still talk to me about so many things. With my personality, I know that absolutely would not have been the case if they were not BF babies. Certainly, YMMV, but PLEASE don't ignore your mother's instinct in terms of the value of the emotional connection.
Best of luck!
M. B.