I just started exercising. I get home and I'll check the scale. then I wait 40 minutes and check the scale again I'll have gained 10 pounds?

Obviously your scale is wrong. That's simply not possible. If you're eating right and working out, I say forget the scale entirely. However, if you're adamant then I would get another one (a good one) and weigh yourself maybe once a week- always first thing in the morning after using the bathroom. Keep the scale in the same place, too. If you move it around it will read differently.

The only way to check your correct weight is to weigh yourself at the same time each day. With exercise,food you have eaten through the day etc can fluctuate your weight.

Weighing yourself is overrated. If you must do it, weigh yourself once a week first thing in the morning. The best gauge for weight is by how your clothes fit.

The chances that your body gas gained any weight, much less 10 pounds in such a short time are infinitesimal!!! Id be looking to get a new scale.

Sounds like your scale is broken.

I suggest a scale where you can find out your water mass, bone mass, and body mass.