Hi,
I am the mom of a six month old boy, and I have breastfed him exclusively for the last six months. He's never had any formula, though we had our breastfeeding troubles in the beginning, including those things you mentioned.
If you have one breast that feels more full than the other, that means you are nursing more on one side than the other. You have to nurse on both sides evenly (for around the same amount of time and for the same number of times) in order to avoid that problem. Sometimes it's a simple as switching sides for every feeding, but you have to take into account when the baby only nurses for a few minutes on one side and for 15, 20, or 30 minutes on the other and make adjustments.
To fix the problem, start nursing more on the side that seems LESS full. That will stimulate that breast to make more milk and cut down on the amount of milk the other breast makes. Your milk production will eventually even out (in a day or two or three). So, nurse twice in a row on the emptier breast and then nurse on the fuller breast once. Stick with that pattern until you even out, and then go to nursing evenly on both sides.
As for the tingling in your nipples near your daughter's feeding time, that's your let-down reflex. In order for the baby to get milk from your breasts, your milk ducts have to get a signal to release the milk. Usually that's caused by the baby's first fews sucks, but sometimes it's stimulated by a regular feeding time, the baby's cry, or even the thought of the baby or her picture. So, take that tingling just as you did - as a sign that it's time to nurse.
I'm an avid supporter of breastfeeding and the bond that it develops between mother and child as well as the boosts in health and immunity, learning and intellectual stimulation, and cost savings! Although sometimes it's a little difficult, I think it's always worth it to stick with breastfeeding because the benefits always outweigh the difficulties. Keep at it, and you'll be successful!
L.