Will upgrade to a full helmet
Good for you. Do it before you crash.
Now I'll just have to scour the threads for helmet opinions.
The one that fits your noggin properly is the one you want. Everything else is fluff.
If money is an issue, think of crash gear in terms of a one time life insurance policy payment that pays for itself while the crash is in progress, not in the hospital afterward.
In addition to the other gear, do not forget crash pants with padding. You have no idea how hard I came down on both knees when that happened. No jeans in existence would have added any impact or abrasion resistance. Jacket, gloves, boots -- everything took a hit that day.
The lack of adequate protection prior to the NH was a calculated but low risk based on the riding I did.
That picture was taken in an extremely low risk environment. The impact foam in the vicinity of the C in KBC was compressed about 3/8" in about a 5 inch circle and the fiberglass shell delaminated a bit to the point that it can now be flexed with your thumb fairly easily. Think about it. -- THEN the belt sander started...