Yes, it's a really bad idea! By "appetite suppressants" I assume you mean amphetamine products. There are other over the counter or over the internet type products but they don't do anything. Appetite suppressants can be addictive, will make you jittery and anxious and will interfere with your sleep, raise your blood pressure and god knows what else. Yes, they will help you lose weight, but you will gain it all back when you stop them and you risk other negative effects such as depression.
Believe me I understand what you are going through. I am slowly but surely gaining weight despite eating quite healthy; I'm significantly older than you which makes it harder. What I would suggest is a few things: If you have any degree of insulin resistance ask your doctor about possibly prescribing one of the drugs that helps with that such as Metformin. If not, consider Symlin. It didn't help me with weight loss at all but it does help many people. There is a Symlin site on here.
As for carbs, when I am able to lose weight it is entirely due to carb reduction. Why can't you say no to carbs? Because they're addictive! More so for some of us than for others. You know for yourself which foods you just can't eat in reasonable servings? The only way to eliminate the cravings is to eliminate the addiction and the only way to do that is not to "feed it". In other words cut out the foods that cause you cravings. It will not be easy but within about 30 days the cravings will disappear. Trust me. I haven't eaten sugar for 18 years and I don't miss it at all.
But what you don't want to do is make yourself feel deprived. I know that sounds contradictory, but if you feel deprived, after awhile you will give in to cravings and that is how you keep losing and gaining. Find new recipes to cook that are relatively low carb but are yummy! Spend a bit more, or take a bit more time and skip the fast food joints at lunch. Instead go to a great deli that has fresh salads. Treat yourself to a night at a nice seafood restaurant - or whatever you enjoy. Replace your old ways of soothing yourself with carbs either with different kinds of foods or treat yourself in non-food ways!
Sounds like you already know there are no easy answers, no instant answers. Appetite suppressants won't help you with your weight loss issue in the long term and could give you more problems than they solve.