Wow, that's a lot of herbs growing from seeds. Personally I prefer to buy them as plants as they aren't that expensive (if you buy in a pack of 6 from B&Q) and esp. stuffs like Rosemary (also easily propagated from cuttings) and Mint (from pulling few plants from someone's garden and repot them). As for parsley, I heard they take a long time to germinate but they're worth it so I don't mind the hassle growing from seeds. It's good your parsley have germinated, maybe I should get on with mine
.
The things with sown seeds is not to overwater or underwater but we can easily get it wrong, I tend to overwater mine too.
Unfortunately it's early for tomatoes (as is for chilli, pepper & aubergine) and they might not germinate unless you use a heated propagator. Believe me, I struggled with my tomatoes until I got myself a heated propagator early this month and even they were no good in 3" pot until I started using very shallow dish. All the best of luck and feel free to post for any queries. We all learn somewhere.