Y., first, you are very much in the thoughts of this stranger. I have been where you are. I am there right now. Please keep reading.
Let's start with the retest on the mammogram: Yes, it could be something, but it also could be a simple calcification that's nothing, or it could be a problem with the way the first one was done. It's fairly common for women to have to have mammograms redone, especially if the radiologists who read them are cautious. Be proactive, even insistent if you have to: Ask if the radiologist will be there at the lab, at the very time you are there getting the mammogram redone,and ask if the radiologist can "read" it while you are still there in the office, so you do not have to go home and wait and wait for a call or a piece of paper in the mail. My ob/gyn suggested this when I had a "call-back" on a mammogram and it helped a lot to have the radiologist read the film during the same visit; I knew that either way,I would have an answer and proceed with whatever happened next. (In my case it was nothing.)If there is a problem, at least you will know that same day.
Second, about the pains. Did you just talk to your ob/gyn or did you get a full breast examination? If not, get one right away. That is vital and your ob/gyn should have insisted on it. If you aren't confident in your doctor, ask to see another one in the practice or find another. OK, here's the deal: People will say "Breast cancer isn't painful, so it can't be cancer," but there is one form of breast cancer, called inflammatory breast cancer, that is painful, and it is very serious; your doctor should check you immediately to rule out this possibility; HOWEVER, Y., it may also be much more likely that you have fibrocystic breasts. Your doctor should be able to tell that with a good exam.
Ask about fibrocystic breast condition. It means your breasts are prone to forming benign but painful fluid-filled cysts (not tumors, which are hard "like frozen peas" as my doctor says). These can really hurt. The pain often comes and goes as the cysts form and disappear; the pains can "shoot" through your breast; the pains may "move around." It's a benign but very scary condition, especially since we all know that breast cancer affects so many women.
Yes, caffeine definitely does encourage formation of cysts in women who are sensitive to it. Even if you think you've never had issues with caffeine -- "it doesn't keep me awake, it doesn't make me jumpy," etc. -- it may be behind the formation of cysts. Knock off all caffeine right away. If you're a big-time coffee or soda drinker you may have to stop a bit gradually but try to eliminate all of it and replace it with water.
If you're fibrocystic, you might also ask your doctor about taking daily vitamin E supplements and supplements of evening primrose oil (available in gel capsules in health food stores and Whole Foods supermarkets). Evening primrose contains lots of fatty acids that help with breast tissue health. The National Institutes of Health web site says evening primrose is "well tolerated" by most who take it. Two ob/gyns recommended for me a regimen of daily vitamin E, evening primrose, a B-complex supplement (all the B vitamins) and of course a calcium and vitamin D supplement which most women need. I think these supplements do help.
Ask your doctor also about your brassieres. I was told to switch to very good quality bras that hold very well, so that the breast tissue doesn't shift around, which can add to pain if you're having a time when the cysts are bad. I haven't always adhered to this advice as the tightness of the bras can be a drag, but it can help. There are specialty bra shops that have professional "fitters" who know vastly more about bras than anyone at Sears or Penneys and who have heard about this condition.
Ask your doctor if you should have a baseline MRI for future reference. My doctor got me one at a place (in Reston, Va.) that specializes in breast-only MRIs. The point wasn't that my doc thought I had any bigger problem; she wanted just to rule out anything she hadn't felt or seen on a mammogram, and she wanted a baseline detailed image. Your doctor may say no or your insurance may say no, but it's worth asking. I have a particularly cautious doctor who says that with this condition she has to "stay on top of" patients' breast conditions.
Most of all, do not let anyone dismiss your concerns or put off seeing you. You alone know what you feel. You alone have to cope with the worry and fear that are still real even if nothing's medically wrong. Take this in your own hands and see what's going on, and don't take no for an answer. I pray for you that this will turn out well. Please post here and let us know how you are. I completely understand your fears and concerns and am sending you my thoughts and prayers along with this advice, Y..