Past 48 hours, I've lost around 4lb. Is this okay? I'm not sure if this healthy, and if I'm just seeing the result of less food in my system?
Beginning of Sunday I was 322.4lb, now I'm 318.5lb, note, the Sunday weighing I was naked (giggity); today I was fully clothed.
First - the changes you've made to your diet are an excellent step, and if sustainable, will really help your progress.
Second - you're 24, so your body is young enough to recover and deal with excess weight far better than my 30-year-old one was, back when I decided to turn things around.
Third - avoid the trap of starting to check your weight too regularly - I'd pick a time, the same time each week for more fair comparisons - and stick to a weekly "weigh-in"
Fourth - the bike is a great idea, do it. Walking is also a great idea, keep doing it. If funds permit, grab some bone-conduction bluetooth headphones, which will allow you to hear traffic as well as your choice of music (which to me is amazing, and I use it regularly with my own workouts!). Also, if possible (and agreeable), grab a fitness tracker watch of some kind, such as a FitBit - mine always motivated me to keep going, or to get up and go.
Fifth - keep us up to date on your progress!
Sixth!! - sorry, I keep thinking of things. Weights, a little bit down the line, are a brilliant idea. They increase muscle, muscle increases basal metabolic rate, which will consume fat as long as you aren't putting in more than you're taking out.
Seventh - patience is your friend. You will slip up, you will be tempted, you will have off days. Accept them all, move on, come back to the course. Also - you'll see some dramatic results early on, which will slow down over time - this just means you're getting closer to your ideal weight and that what you're doing is working - keep at it, and give it at
least 6 months before making any judgements.
I'm very pleased that you're getting out there and getting healthy, dude. Flipping well done. I'd high five you if I was in the vicinity.