Is Imbolc over? Did I miss it?

Short answer...No.
Depending on your sources Imbolc might be celebrated on February 1st, which is sort of traditional in North America. Or it might be celebrated on February 2nd, which is Candlemas Day, a Christian version of Imbolc. Or if you look at some astronomical data you might find that it is on February 4th. info found here
A friend of mine says her coven celebrated on the 2nd, according to their astrological data.
Many people, out of practicality, celebrate the Sabbats on their day off work, regardless of the actual date.

So, I wanted to take this opportunity to talk about my personal take on the Sabbats.
Many of us follow the Celtic calendar, more or less. Also known as the Wheel of the Year, this calendar shows us 8 Sabbats. Four of them are Sun Festivals, sometimes called the major Sabbats. These are the solstices and equinoxes. In my practice, the exact day and time that these fall on is important.

Some might say that modern science can pinpoint the exact moment of these occurrences, but how could ancient peoples have done this? So why should it be important?
All over the world are carved stones and piles of rock and carved crevices and holes in stone that line up precisely at the moment of these astronomical events. How they did this is not as important to me as the idea that they felt it was important to know the exact moment and mark it.
I try to mark these days on the exact moment also. A formal ritual on the day, if not at the exact time, has special meaning for me.

The other four Sabbats are known as the Fire Festivals or cross quarters.
In my practice the exact dates and times of these festivals are not as important as observing them.

In my thinking, the Sun Festivals are about what goes on in the heavens and the Fire Festivals are about what goes on here on the earth. The Fire Festivals are about celebrating the actual changes in the seasons and it is more important to fully appreciate these changes than it is to celebrate on a particular day.

Imbolc is an old Gaelic term that translates as 'ewe's milk' and refers to the beginning of the lambing season. This runs through mid-February and for the ancient Celts was the first tangible sign that spring was actually on its way.
Spring, the fertility of the flock, the turn of the wheel all were worthy of a celebration or Fire Festival.

In celebrating this day Brigid is often honored. Brigid is a Fire Goddess. She brings spring by breathing fire into the frozen earth.
Fire is the Element of creativity and passion. This is a good day to organize a ritual around creativity.
Do you need a boost in the area of creativity? Could you use her help in freeing up some creative feelings? Would you like to thank her for the creativity that you have and enjoy? Are you starting a new project/job that would benefit from a boost in creativity? Try your own variation of this:

Cast a circle, call the Elements to stand guard, light candles dedicated to Brigid.
Call on her and ask her to be present.
Take a few minutes and think about Brigid and her roles of shepherdess, fire goddess, healer and warrior. Think about where your own creative abilities or aspirations lay.
Make an offering to Brigid.
Sing, dance, draw, paint,write, cook, care for your plants, visualize the perfect fashion outfit, the perfectly decorated room, the abundant garden..... offer her, physically or mentally the best of your creative talents.
Now ask her to continue to bless your abilities and help you to find ways to grow. Meditate on this, visualize what you want to do, be receptive to any suggestions about how to grow and improve.
Thank Brigid for coming, put out the candles, let the Elements go and disperse your circle.

Happy Imbolc.