Hello,
I cannot confirm anything with examination,but it looks like milaria rubra or sweat dermatitis. Tiny red spots with itching and pricking sensation are the characteristic appearance of this rash.
Avoid using any lotions and creams for the meantime.Use a mild cleanser with moisturizing properties like Cetaphil. Also use cotton clothes and change the clothes twice if there is any increased sweating.Try keeping the skin free of sweat as far as possible. If the symptoms still persist then you can apply mild steroid like dermacort.If there is any itching antihistaminics like Benadryl or Claritin can be taken.
I hope it helps.Take care and pls do keep me posted on how you are doing or in case you have any additional doubts.Kind regards.