As Alex777 put it, this is meant to be in the nicest way helpful advice, because when it comes down to it, you will have the ultimate decision on what you do and each of us accept different levels of risk.
Part of diving (to me) is learned behaviour and repetition of muscle memory, teaching yourself what you hope will become "instinctive learned responses", that way when something goes wrong, you have a better chance of survival.
What I mean by this (for example) is that I may practise flooding/removing mask each dive, swopping regs to back up and then back again each dive etc, so that if something happens, you have that mental and muscle memory to fall back on.
Because until something goes wrong, and we all hope it never will, you never know how you will react; but being able to partially rely on the muscle memory of practised skills (I call it creating the diving instinct) can make the difference when things go wrong.
So the question I would ask myself in that situation, is after 21 dives, do you have that automatic muscle memory and experience of things going wrong?
Have you had the time to practise a skill as you swam along on each dive until it was boring and routine or have you not really done any since the course?
Diving in new and untried situations increases mental stress, even if you don't realise it at the time. which increases the chance of mistakes/risks happening.
And it sounds from the post (and apologies if I am wrong) that its a potenitally a new dive site, new area, first shore dive, first solo dive and then if the answer to the question above is not really, that's the 5th item that could add to increased stress for the dive.
I know, for me, that would equate to a big red flag and I'd look to see if I could reduce those "stress factors" down, but as I said to start, we all have our own level of acceptable risk, and I accept I am a different diver to you, but that's just the thought pattern I'd go through if I was considering the same dive.
What ever you choose, may you have many years of safe happy diving