Pfitz is great to follow. Your goal should be to get to June healthy and feeling good. Structure with a running group would be a good idea. But the biggest advice I would say to you is:
a) Never run a week with more than two not-easy efforts. Steady, tempo, threshold, VO2_max are all not easy efforts. You can do a long run at EASY pace (probably 9, 9:30), plus a steady/tempo and a faster effort, or incorporate the steady/tempo effort into your LR (4-5 easy, 6 steady, 2-3 easy) and do one additional workout. Pfitz 18/55 is tough if you've never done it, so don't overdo it before starting it. Doing a steady LR + two more non-easy days is not a good idea.
b) Don't change anything drastically right now and add crazy amounts of miles or tons of speedwork. Just keep it simple.