Caffeine Woes

Okay, all you mommas...I have a question.

I've been told by my doctor and by many things that I've read, that a certain amount of caffeine is okay during pregnancy. Specifically, any amount under 200 mg is said to be okay. I drink one 8 oz. can of Dr. Pepper in the morning around 5-6 days a week. Right now, it's less of a want for caffeine and it feels more like a need. I'm working long days and struggling to get enough sleep; thus, I'm struggling to wake up in the mornings. Dr. Pepper's website says that an 8 oz. can contains 28 mg of caffeine, which is well below my suggested daily intake.

However, the worry wart in me just wonders if I'm poisoning my precious peanut. Yes, I know the doctors say that as of now they believe that a small amount of caffeine is okay, but I still stress.

Any advice out there?
Have you heard anything different, good or bad, about caffeine during pregnancy?
Do you have any alternatives that you've tried that might wake me up in the mornings?