Answer: Tomato flowers have all the necessary parts for self-pollination so a gentle shake of the plant is usually all that's needed to transfer the pollen from the male to the female parts of the same flower. If you want to ensure success, you can hand pollinate by gently touching the insides of each flower with a soft brush. I'd wait until the flower has been open for a full day before transferring pollen with a brush. Once it's pollinated, the flower will begin to close and fruit formation will begin. The "closed" part of the flower you mention is normal -- it produces star-like outer petals, and the center of the flower contains the sexual organs, all clustered together.
Hope this provides reassurance! Sounds as though you're giving your tomato plants plenty of TLC and they should reward with with sweet, tasty fruit.
Q&A Library Searching Tips