ya i got the same problem sometimes (awake nights, sleepy days, but a power nap usually clears that up which is fine as long a you dont over sleep, 20-30 min max powernap unless you want to screw your night pattern up)
as for meditation and sleeping. if you feel tired in your meditation, like even 5 or 10 min in, you should go down and sleep. this means your body needs the extra rest. then meditate for 5 mins when you wake up
if you dont feel tired or anything just do your regular meditation schedule. meditation should be and lead to an awake alert state, not sluggish and tired, like i said if you get tired, dont power through it then nap.
and you shouldnt go from meditating into a long 7 hour sleep either, it should lead into a power like i said if you got tired, or if your rested enough, you should be awake through the whole thing and crisp after.
eating healthy - man, you really need to add fruits and vegetables into your diet lol. if your diet at the moment is void of those, then your body is lacking in a lot of essential vitamins and minerals that it needs to function optimally. pasta and bread, any refined carbs, i would try to kick for good. they are just plain no good for you, theres a lot of science behind it, plus they are genetically modified. theres a book called wheat belly i hear everyone talk about, ive never read it because i just know the basic tenet of it, dont eat refined carbs, easy enough.
and you dont necessarily have to eat something different every day. ive eaten eggs (organic if i buy them when im in the area), organic SPAM (which is cheap as fuck i bought a bag that will last me a week or more for 3 bucks) and fruit (which isnt expensive either) everyday for breakfast, pretty much the same thing everyday for the past few months. sure its nice to change it up, but you dont HAVE to.
buying junk food is a lot more expensive than eating healthy. a fucking thing of fruit rollups is like 8 bucks and its bullshit food. fruits and vegetables arent expensive, and the some things that are more expensive, like broccoli or cauliflower, or dragonfruit (which i love), but them here and there, but looks for the deals. when the deals are on thats when you buy them. and contrary to what your probably thinking, a load of chicken is a lot more expensive than fruits or vegetables. 6 bannanas will run you like $1.50, thats nothing. sweet potatoes are cheaper than normal ones (where i live) and they are better for you too. buy fruits and vegetables man dont kid yourself that they are all to expensive because they aren't, some are more than others but still, and they taste so dahm good. and you mean to tell me your parents only feed you pasta bread chicken and potatoes? they dont eat fruits or vegetables either?
and check the reduced rack, theres always good shit on there thats super cheap, i always do and you always find something thats good, and eat it that day or the next or cook with it.
well for stress ill let you deal with that, or maybe try some EFT tapping or something, it works with everything, ive had results with it, it works pretty good sometimes. and it isnt all pseudo-science either its been researched now and actually does have an effect.
exercise is good, you dont necessarily need to do cardio, as long as you keep a pretty up beat pace when you lift weights, it will acheive the same results as a cardio session because your heart beat is up which = fat burning and cardio. which is perfect bcuz like you said its winter and running on the spot and jumping 10000 jumping jacks is borning as fuck lol (but it does work your calves decently).
tap waters fine unless its been flouridated and all that bullshit. bottle water is a waste of money unless the tap water is poison. like i said, find a well or a spring, do a little research on google theres lots of websites out there to help, i had found an all america one before and they are all over the place (just get the water tested first to be sure its safe).
omega 3's, get some, any health food store will have them, there are brown and golden ones, apparently the brown ones are better slightly for your health.
read the power of now or a new earth by eckhart tolle, those are good books
cheers buddy hope that helps