Recently, i've had a few mushroom like things popping up in my tomato plants and i'm not sure what they are and what i should do about them (can i still eat the tomatoes)?

Just some fungi spores in the compost or manure you used. They grow in damp conditions. Shouldn't be a problem unless you plan to eat them, in which case I strongly suggest expert ID. If they bother you, lightly cultivate the top of the soil and they'll disappear and feed your tomatoes. Which are perfectly safe to eat.

Welcome to NGA! I hope you can get an answer to your question; however, you might want to post this in the Tomatoes forum (assuming there is one) rather than the Roses forum.