I am newer to gardening and have been trying to grow tomatoes from seed this season. I am noticing that some of my container tomatoes are slowing in growth and are starting to get these brown irregular spots on them... and the branches seem to be pointing downward. Your help is very appreciated!

I am not sure if it is a disease, pest or maybe the soil I am using. We headed to San Pedro for some free mulch and folks were telling us it was decomposed enough that it was like compost and we were using that to plant our tomatoes. Not sure if that might be our issue

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