Gained a pound....confused.
 

So my daily caloric intake is somewhere around 1250-1400 and I've been walking 2.5 miles every day (except one) in 30 minutes, so pretty brisk. I keep my heart rate up during that workout. I've been doing this for two weeks straight now, the past week I lost 10+ pounds. But now I gained a pound back this week. Is it possible that it is muscle? Or should I change something?

Most likely, you were dehydrated.
You should weigh yourself once a week at the same time to even out flucuations.

Exactly. Weigh once a week at most. I see day-to-day fluctuations of several pounds sometimes, it's nothing to worry about. An extra salty meal one day can pack on a couple pounds of fluid the next day. The day after, it's gone.

Regards,
Michael

That's the thing though, I do weigh myself every week, not every day.

It can still be a normal variation.

As mecompco pointed out, a little extra salt, a lot of extra water and you're up a pound.

This. It would be nice if we could gain a pound of muscle in a week but that's not gonna happen.

So what do you suggest I do? Nothing?

yes, just keep on keepin' on.

Exactly, just keep on keepin' on. Look you KNOW what your deficit is, and it's been working. Trust the numbers and your losses will even out. There WILL be plataues and normal fluctations along the journey. You need to focus on the averages and keeping on your plan.

I'll wager that your weigh-in next week will be more to your liking.:)

Regards,
Michael

Alright sounds good.

Are you just doing cardio alone or are you strenght training also. If not, then maybe think about doing some weight training and it will help you burn more calories and tone your body and add some lean muscle mass

I was just doing cardio, I'm back on track now. I think maybe it was too many carbs and not enough protein.