First of all, there are 3 kinds of "colocação pronominal" in portuguese.
Próclise, Mesóclise and Ênclise.
for the first sentence, the correct is "eu não me deito agora", because negative expressions (não, nunca, jamais, nada, ninguém, nem, de modo algum) "attract" the pronoum to the left of the verb (próclise).
for the second one, you'll want to use (again) próclise, because you use it in interrogative sentences. so, the sentence would be "tu te chamas pedro?"
you'll use ênclise only in few situations, like:
1) With verbs in infinitive:
- Entregar-lhe.
- Não posso recebê-lo.
2) Verbs in the beggining of the sentence:
-Entregaram-me as camisas.
3) With verbs in affirmative imperative:
-Alunos, comportem-se.
4) With verbs in gerund:
-Saiu deixando-nos por instantes.
5) With verbs in impersonal infinitive:
-Convém contar-lhe tudo.
OBS-1: if a preposition or an "attractive word" comes before the gerund, próclise will occour:
- Em se tratando de cinema, prefiro o suspense.
- Saiu do escritório, não nos revelando os motivos.
OBS-2: ênclise in verbs in the future or participle is ALWAYS wrong:
- Tornarei-me……. (wrong)
- Tinha entregado-nos……….(wrong)
TIP: if you are not sure if you should use próclise or ênclise, use próclise. in 90% of the time, it will be correct.
talking about mesóclie, it's not used at all, even in books. you can find them written in some old books or poems, but nobody uses it. so, you can, for now, just ignore it.
hope i could help you ^^
see ya