As everyone else has said....keeping hydrated is key. I had this early in my second pregnancy (during the 2WW, actually - I think it was a symptom but I didn't pick up on it at the time). Don't be tempted to take Pepto Bismol.....a pharmacist advised me that it's got aspirin in it....a no no to take during pregnancy - and while breastfeeding, too, incidentally!!
I am currently pregnant with my 4th baby and had diarrhea with all of them the whole time, a lot of pregnant women get constipated, but some get diarrhea instead or get both! as long as you are doing ok with liquids you should be fine, the only time i have had to much trouble with it was when I have really bad mornign sickness and vomiting and was getting dehydrated! if you really don't like it talk with your doctor there are I think 2 over the counter medications that you can take to help with it (one is immodium, I can;t remember the other one) but it's not a big concern usually! good luck and congratulations!
Diarrhea is common in Pregnancy and is not something You should be over concerned about. It can be a side effect of pregnancy for quite a few people.
If You're still concerned about it You can always see Your doctor but try not to stress over it.
Make sure You're drinking plenty of fluids and keeping your fluid intake up and try adding more solid foods to your diet.
Diarrhea and constipation are common side effects of pregnancy. It's not going to hurt anything so long as you keep yourself dehydrated. Drink plenty of fluids and try eating some yogurt to help restore the normal balance of bacteria in your digestive system. As long as you are getting the fluids you need it will not have any affects on the baby.
I had it in early pregnancy as well. It's not bad, as long as you're keeping your body hydrated. If you start having frequent vomiting at the same time though, you'd more than likely need to go to a doctor to make sure they give you the fluids your body needs. You can try eating fiber rich foods which should help to regulate and clear it up. It normally doesn't last too long.