Need some help with weight loss

I'll start off saying I lost like 70 pounds last year when I was in this military-type camp(got back home in November). Once I got back home though I stopped working out for a while. I have gained like 5-8 pounds since I've been back. So I'm trying to lose weight now and its tough. So these past 2 weeks I cut off soda, and I only drink water. But I still eat sorta the same little less. I go walking at the park with my dad 5 miles. On the days hes off maybe 1-3x a week. At home I lift weights, do squats and every other day I do this pilates tape. Is it possible to lose weight by just doing weight lifting and the pilates tape. I went to this one sites and they say you gotta do cardio etc. etc. And lifting weights will just make you bigger. But running on the threadmill isnt as fun as lifting weights. So I was wondering can I just do that to lose weight. Also do I have to start going on a diet. I don't eat fast food or anything just what my mom cooks. Like chicken, rice, mashed potatoes, some type of vegetable. I did eat a donut or 2 yesterday which I know I shouldn't have. I don't wanna weigh myself on a scale because I'll be mad that I still weigh the same. My muscles have gotten noticably bigger. But I'm not sure if I'm losing fat. Any advice? Oh and I'm 17 male if that helps any?

Hi and Welcome to IM!
Congrads on your weightloss last year.

would you mind doing a favor and posting your current diet..
ex:
meal 1
meal 2, etc
.. note the time of the meal , what you ate, and how much. Also when you worked out.

what are your current stats?

here is some very beneficial info for you as well:
http://69.93.187.54/showthread.php?s=&threadid=21113

as for your training- are you following any sort of structured split.. perhaps you could elaborate a bit furthur on what you are doing.
and no cardio is not essential for fatloss. diet plays a HUGE role in progress.

Well for exercise. I do 20 pushups then 15 then 10 then 9..8..7..etc. to zero. Then I do situps same thing. Squats I do from 10. This 25 pound weight I lift it straight up and down. 40...30..20.15.10..9.8.etc to zero. I do that for each arm. I dont really know the names for exercises since im new. And I walk 5 miles with my dad when hes off maybe twice a week. I take this vitamin supplement its liquid and I take two tablespoons a day. It has all the animo acids, herbs, etc. in it. Well today I eat a piece of chicken and a roll. And I think I eat a leg early this morning. It's leftover from last night. And I only drink water I'm trying to drink a gallon a day but I usually only get to 3/4. For dinner I don't know what I'm having yet.