Don’t feel bad about this! Some nights I can recall a huge number of dreams, while once a week or so I remember no dreams whatsoever! Dream recall still to this day takes focused effort for me. If I don’t focus, I’ll get almost nothing.
Upon the moment of waking, try to lie perfectly still and reach for any fragment of dream that you can find. Once you’ve got something, try to work backward and forward from there as far as you can without physically moving your body. This may take no more than 30 seconds or so, but it’s worth making sure you’ve got a good grasp of the dream before you start disrupting yourself by moving around and looking for your journal.
For many people, there also tends to be a habit of waking up thinking about the day’s concerns and what is ahead of you. Try to make your first thought upon waking to a) remember what you were just dreaming and b) reality check! That other stuff can wait.
A great technique to try is the SSILD technique, described in this thread. I hesitate to call it “easy” because it does require waking up in the early morning but the instructions are straightforward. This technique has had a lot of success. (Speaking personally, it’s where I get most of my lucid dreams from.) Its author is also very experienced and offers a lot of helpful advice.
Edit: Just noticed this! Big congratulations!! That is awesome. My first was very brief too. Now you’ll be even more ready for your next lucid dream. Great work.