The color of the line is insignificant. Pregnancy tests can only tell you if you are pregnant. The darkness of the line is no indication of how pregnant you are or how far along you are. You can use the brand tests, even from the same box and get a lighter or darker line any time.
The phantom calls that you have recieved, also known as ghost calls is usually caused by either a poor quality phone line, aka has a high amount of noise or foreign battery due to the line or your on an older copper line.
In the Missed Calls directory on your phone, you can edit a number so that you can easily dial back a missed long distance call. For example, if you missed a call from 800-435-7270, it will show up as 8004357270 in your Missed Calls directory. If you select that call from the directory and press the Dial softkey, you will get a message that your call cannot be completed as dialed.