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.
Static interference and harmonic distortion are electrical disturbances caused, for example, by air conditioners, vacuum cleaners, hair dryers and cordless phones. A leading cause of electrical trouble for home computers, they can also create serious problems for stereo, radio, security and phone systems.