Is grabbed a pronoun

No, the Word 'grabbed' is the past tense of the verb to grab (grabs, grabbing, grabbed).

The Word grab is also a noun, a Word for a quick clutch or attempt to seize; a sudden snatch.

Examples:

They began to grab what they could when the downpour started. (verb)

Jack grabbed the cooler with the beverages. (verb)

Jill's grab netted the Sandwiches and the salad. (noun)

A pronoun is a Word that takes the place of a noun in a sentence.

Example: They began to grab what they could when the downpour started.

The pronouns 'they' take the place of the nouns 'Jack and Jill', the picnickers.