I just want to 2nd what nomadmom said. Go see a doc ASAP!!!!!!!!!!! It sounds VERY much like underactive thyroid (note: I'm not a medical provider but do have underactive thyroid myself). Especially the glands under your neck being swollen. It is a simple easy quick blood test to test your TSH level (thyroid stimulating hormone). If you have hypoactive thyroid, you will need to go on synthetic thyroid hormone, which is one pill a day, no side effects because what it is doing is giving you hormones that you are missing, not extra hormones or anything. Based on the symptoms you describe, it sounds to me like you have a VERY underactive thyroid, because your symptoms sound extreme. Please please go asap, it's such an easy problem to solve, but if you don't get it treated, it can become more severe.
Some info on the TSH blood test: Normal TSH should be between .5 (or close to that) and 3. Anything over 3 indicates underactive thyroid. Some docs are still "old school" and follow guidelines that TSH has to be greater than 6 to treat. However, if your doc says this, FIND ANOTHER DOC!!! Mine says that she's seen over and over that people between 3 and 6 feel much better when they go on meds and get down below 3, and she says this is what most folks in the field recognize now, but not all.
i fourth or fifth the thyroid check. i'm hypothyroid (low), too. you do need to get it treated if it's low. it's very easy, but untreated it can lead to a lot of more severe problems than you're already having including depression and rampantly long term untreated low thyroid can lead to decreased mental functioning -- so basically you get dumber. i feel fine with the synthroid and if that's your problem i'm sure you will, too. i was cold all the time before. i never had some of the other symptoms like dry skin and hair and constipation, but lots of low thyroid folks report them. low thyroid is common after pregnancy, too, and more common in women than in men. oh, the swollen neck gland can be the thyroid itself. it's in the front of the neck near your adam's apple and when swollen can become a goiter and be visible from the outside as well as being able to feel it by palpating. i've found that sometimes i can feel a swollen feeling in my throat if that makes any sense.
sorry this is so disjointed, but dd needs my attn. gotta run, but let us know if you get it checked out.